@conference {3738, title = {3738. Aft Perpendicular... An Afterthought?}, booktitle = {81st Annual Conference, Savannah, Georgia}, year = {2022}, pages = {12}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Savannah, Georgia}, abstract = {

How do you define the length of a ship? What is the definition of aft perpendicular? From the Principles of Naval Architecture (PNA), the definition for the location of the aft perpendicular {\textquotedblleft}is at the aft side of the rudder post, centerline of the rudder stock, or at the intersection of the design waterline with the aft end of the vessel.{\textquotedblright} However, for U.S. submarines, the location of the aft perpendicular has not always followed PNA{\textquoteright}s definition. The location for a submarine{\textquoteright}s aft perpendicular has been at the end of the thrust device or at an outdated feature. This paper will examine the technical details, design maturity and timeline, and implications of how the aft perpendicular on a submarine is defined.

}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3738/buy}, author = {Scott Daley and Rob Dvorak and Matt Marburger} } @conference {3776, title = {3776. Harnessing Historical Company Data for Estimating Weights of Customized Commercial Workboats}, booktitle = {81st Annual Conference, Savannah, Georgia}, year = {2022}, pages = {33}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Savannah, Georgia}, abstract = {

Robert Allan Ltd., Canada{\textquoteright}s most senior Naval Architecture and Marine Engineering firm, specializes in the design of ship-handling tugs and other workboats for a global clientele. On average one to two vessels designed by the firm are launched every week. Almost every vessel is tailored to meet the needs of the client, even if it is based on one of several common hull types. This design flexibility presents a challenge when it comes to estimating weights efficiently and accurately. Fortunately, Robert Allan Ltd. can draw on a significant historical database that can be leveraged when estimating vessel weights and centers of gravity for new projects. Over the last six years, the weight engineering team has worked to build a more efficient, rigorous, consistent, and accurate weight estimating procedure for tugs and other commercial workboats while still allowing for client-driven design customization. This paper summarizes the process of collecting and utilizing historical data to develop a tool to estimate weights and centers of gravity for a new vessel based on the limited number of inputs available at an early phase of design. It will also address how the development of this tool, which has become a key component of the firm{\textquoteright}s weight estimating process, has revealed key areas where more specialized tools are required to improve accuracy and efficiency. This has led to Robert Allan Ltd. developing a collection of specialized weight estimating tools and guidelines that address these key areas and cater to the different design phases. Although these tools have evolved to a point where they are widely used throughout the firm, they continue to be modified and upgraded to meet new requirements and include new data.

}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3776/buy}, author = {Chandan Deol and Lindsay Johnston} } @conference {3762, title = {3771. A Look at Inclining Experiment Heel Angles: Measurement Tools and Sensitivity}, booktitle = {2021 SAWE Tech Fair}, year = {2021}, month = {11/2021}, pages = {27}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Virtual Conference}, abstract = {

An inclining experiment is used to indirectly measure the vertical center of gravity of a ship by measuring resultant heel angles for a given weight moved athwartships. The methods for measuring these angles are considered tried and true even though the uncertainties of their accuracy and precision are not well understood. This paper explores the impact of errors from traditional inclin- ing methods and compares them with modern methods. The paper looks at a simulated inclining experiment and explores the change in results when errors are introduced into the measurements. It then looks at electronic inclinometers used in an actual inclining and discusses how that data can be analyzed and how that might affect the results of the experiment. Finally the paper dis- cusses the advantages and disadvantages of old and new methods and provides recommendations for improved results from future inclinings.

}, keywords = {03. Center Of Gravity, 13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3771/buy}, author = {Tellet, David} } @conference {3772, title = {3774. Weight Control For Floating Wind Installation}, booktitle = {2021 SAWE Tech Fair}, year = {2021}, month = {11/2021}, pages = {10}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Virtual Conference}, abstract = {

Floating offshore wind is a growing market within the renewable energy sector. The floating offshore wind turbines give access to deeper water sites, with minimal visual impact from land. The paper includes the weight control requirements for Spars, barges, semi submersibles and Tension Leg Platforms (TLPs) as floating wind platforms.

There are weight control challenges for the various substructure types during the temporary phases of construction and offshore installation. An accurate assessment of the buoyancy of the floating wind turbine for different drafts and trims is required. Allowances need to be included in the weight calculation for temporary buoyancy, sea-fastenings and grillage.

Weight control for installation has an influence on the weather window for the floating substructures during transportation to the offshore site and mooring and electrical connection. The paper will cover weight calculation methods during early design, detailed design, construction, installation, operation and demolition.

The installation process for a floating wind turbine varies with substructure type and this paper will give an overview of the weight control requirements for loadout, ocean transport and mooring connection. The floating offshore wind turbine weight and centre of gravity has a direct bearing on draft, intact stability and motions. As part of the weight control process the centre of gravity and radii of gyration need to be accurately determined for each stage of the installation.

}, keywords = {13. Weight Engineering - Marine, 24. Weight Engineering - System Design, 35. Weight Engineering - Offshore, Student Papers}, url = {https://www.sawe.org/papers/3774/buy}, author = {Crowle, A. P. and Thies, P.R.} } @conference {3741, title = {3741. Finding the Balance Between Accuracy and Practicality in Deadweight Survey}, booktitle = {2020 SAWE Tech Fair}, year = {2020}, month = {07/2020}, pages = {24}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Virtual Conference}, abstract = {

Deadweight audits are exercises required to calculate the vessel lightweight by deduction from the actual ship weight. Depending on the size of the vessel, they can take a few hours to several days. Minimising the duration of the exercise should be prioritised since accuracy of the result is connected to avoidance of changes in the recorded vessel{\textquoteright}s configuration during the audit. This leads to a compromise between precision and the accuracy that can be achieved: estimating the weight of the deadweight based on experience is the quickest method, weighing everything with calibrated scales is the most precise. An intermediate solution is to find the deadweight partly with estimates, partly with weighing.

Experience with all three of these methods showed that accuracy can be achieved even if relatively poor resolution is accepted, if some precautions are taken when recording the weights.\ 

This paper presents three study cases and the calculation of uncertainty in the deadweight that derived from the different approaches. The uncertainty and the time spent to complete the audit are used to define an efficiency estimator to rate the deadweight audit.

The conclusion is a method to upgrade data recording that allows production of a more meaningful result.

}, keywords = {08. Weighing, 13. Weight Engineering - Marine, 21. Weight Engineering - Statistical Studies, 35. Weight Engineering - Offshore}, url = {https://www.sawe.org/papers/3741/buy}, author = {MacFarlane, Colin and Bucci, Manuela} } @conference {3711, title = {3711. A Century of Submarine Mass Properties}, booktitle = {78th Annual Conference, Norfolk, VA}, year = {2019}, month = {05/2019}, pages = {41}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Norfolk, Virginia}, abstract = {

This paper takes a chronological look at submarine milestones during the last century and discusses how the evolution of submarine design affected mass properties engineering including weight control processes, management of mass properties, technical authority, and stability and buoyancy requirements. The paper discusses how the movement of submarine design from boats that can submerge to submarines designed for near constant submergence changed performance requirements including mass property limits. It discusses how the Cold War and nuclear power influenced submarine design and how this affected mass properties requirements and practices including deliberate margin depletion and reduction in service life margins. The paper includes some thoughts on future submarine designs and how those may affect mass property management practices.

}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3711/buy}, author = {Tellet, David} } @conference {3715, title = {3715. Negligible Weight Quantification for Surface Ship Weight Surveys}, booktitle = {78th Annual Conference, Norfolk, VA}, year = {2019}, month = {05/2019}, pages = {12}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Norfolk, Virginia}, abstract = {

Shipboard weight surveys are routinely performed for surface vessels across the spectrum of marine industries from small pleasure craft to large surface combatants. These surveys are typically part of a vessel{\textquoteright}s stability test (weight survey \& inclining experiment) usually required as part of the vessel{\textquoteright}s delivery/acceptance or during its service life to confirm the safety of the vessel and/or crew/passengers has not been compromised from post-delivery modifications or inevitable weight \& KG growth. These stability tests may take a few days to a few weeks, with a large portion of the effort attributed to the weight survey itself. Further, a large portion of the survey consists of inventorying smaller items which typically constitute a relatively small portion of the overall weight nor may have any appreciable impact to the overall results of the stability test.

To date (to the author{\textquoteright}s knowledge), no official guidance or recommendation(s) exists on what or how to quantify as negligible weight(s) for the purposes of a weight survey. This guidance, if available, may reduce the time required for survey and save considerable time and resources without appreciably changing the end result and/or conclusion.

With limited availability/diversity of actual ship survey data, the analysis will focus on the required precision of the stability test based on accepted requirements documentation. This analysis will consider the size of the vessel which directly impacts the design{\textquoteright}s sensitivity to weight, as well as the practicalities associated with the existing practices of shipboard surveys such as availability of the vessel or qualified personnel. In addition, industry guidance on human engineering design will be used to establish {\textquotedblleft}rules of thumb{\textquotedblright} for determining item weights and/or their potential impact to the results to aid in shipboard surveys.

}, keywords = {13. Weight Engineering - Marine, 25. Weight Engineering - System Estimation}, url = {https://www.sawe.org/papers/3715/buy}, author = {Roach, Greg} } @conference {3717, title = {3717. Evaluating a CoG Envelope Using a Probabilistic Approach}, booktitle = {78th Annual Conference, Norfolk, VA}, year = {2019}, month = {05/2019}, pages = {15}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Norfolk, Virginia}, abstract = {

In the Energy and Chemicals Construction Industry, many onshore projects are using modular construction. \ This type of construction requires that the modules be transported from the fabrication yard to the project site. \ The fabrication yard may be distant from the project site, thus requiring a combination of ocean transportation and land transportation. \ 

To verify the design, the structural analysis uses a given design weight limit and center of gravity (CoG) envelope for the various modes of transportation. \ The size of the CoG envelope can influence the strengthening requirements for the structure during the transportation phases. CoG envelopes are typically set as a percentage of the module length and width. \ In special cases, a probabilistic approach could be used to reduce the typical CoG envelope size for reducing the amount of strengthening requirements while also quantifying the risk to the project for reducing the size of the CoG envelope.

}, keywords = {13. Weight Engineering - Marine, 21. Weight Engineering - Statistical Studies, 35. Weight Engineering - Offshore}, url = {https://www.sawe.org/papers/3717/buy}, author = {Hundl, Robert J.} } @conference {3718, title = {3718. Center of Buoyancy and Center of Gravity Measurement of a Submersible Vehicle}, booktitle = {78th Annual Conference, Norfolk, VA}, year = {2019}, month = {05/2019}, pages = {16}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. Weight Engineering - Marine ; 21. Weight Engineering - Statistical Studies }, address = {Norfolk, Virginia}, abstract = {

Stability of submersible vehicles is dependent on the relationship between the center of gravity and center of buoyancy locations on the object. Improper relationships between the two can reduce performance and adversely affect the mission goals of the vehicle. Measuring these values can reveal variations from the designed values that may have been introduced during the manufacturing or assembly process. These values can also change in modular submersible vehicles which allow swapping or modifying components based on the needs of their mission. Errors associated with an improper relationship may not arise until sea testing, which may lead to the need for vehicle disassembly in order to shift or change ballast weights of the submersible.

This paper examines a measurement system designed to measure the center of gravity and the center of buoyancy of a submersible object using a hanging weight and center of gravity instrument. The method demonstrated is applicable for vehicles ranging from a few pounds to upwards of 15 tons. With proper fixturing, the machine is capable of measuring center of buoyancy and center of gravity in all 3 axes, which can help determine lateral, longitudinal, and directional stability of a part. This paper outlines a process for measuring submersible vehicles (with negative or slightly positive buoyancy) to determine weight, buoyant force, center of gravity, and center of buoyancy.

}, keywords = {13. Weight Engineering - Marine, 21. Weight Engineering - Statistical Studies}, url = {https://www.sawe.org/papers/3718/buy}, author = {Blair, James} } @conference {3719, title = {3719. Modernising Ship Stability: Lightship Evolution Diagnostics with In-Service Stability}, booktitle = {78th Annual Conference, Norfolk, VA}, year = {2019}, month = {05/2019}, pages = {24}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Norfolk, Virginia}, abstract = {

Lightship mass and center of gravity are the basis for assessing ship regulatory stability and the maximum payload that the ship can load results from this assessment. \ Knowing the ship mass and centre of gravity is therefore of utmost importance for both commercial and safety reasons.

It is known that, over time, both these quantity change. At present, changes in the lightship are addressed by five-yearly audits that may lead to an inclining experiment - the traditional way to measure ship mass and centre of gravity. \ The time gaps are filled with estimates based on weight control which can be shown to be a {\textquoteleft}random walk{\textquoteright} process. This means that, temporarily, undetected worsening of the ship stability might occur.

Draught measurement provides immediate feedback of the accuracy of the estimate of weight change, provided draught sensors are adequately maintained. \ Evidence of change in the vertical position of the lightship center of gravity is not, however, obvious.

In-service stability measurements, integrated into the vessel{\textquoteright}s operational routine, directly estimate the vessel VCG and can diagnose changes in the lightship vertical moment using statistical process control techniques. \ Changes in the progression of mean values of Deadweight and Lightship vertical moment are used instead of records of weight changes to build a model of ship stability over time with uncertainty on the mean value decreasing with increasing number of measurements. \ Weight control remains important to characterize the changes and discrepancies from the loading program can be used to identify sensor failures, defective estimates of cargo deadweight and Lightship changes.

This paper briefly reviews conventional techniques (referring to previous Conference papers). \ It then discusses attempts to perform conventional inclinings at sea and the difficulties in obtaining precision, before setting out the methods of in-service stability assessment, techniques for analysis of the results and finally the control limits that can be used to trigger further investigation. \ The technology is suitable for autonomous vessels.

}, keywords = {13. Weight Engineering - Marine, 21. Weight Engineering - Statistical Studies}, url = {https://www.sawe.org/papers/3719/buy}, author = {Bucci, Manuela and MacFarlane, Colin} } @conference {3698, title = {3698. Weights, Center and Inertia Modeling of the Sinking Analyses of the El Faro}, booktitle = {77th Annual Conference, Irving, Texas}, year = {2018}, month = {05/2018}, pages = {22}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Irving, Texas}, abstract = {

The analysis of a ship experiencing downflooding must begin with a careful understanding of the unflooded and undamaged condition as a point of departure. From there the consumables can be adjusted vs time and the flooding can be added to successive weights calculations to build out the probable downflooding and stability progression.

The 790 foot SS El Faro was lost with all hands October 1st, 2015 off the Bahamas near the eye of Hurricane Joaquin, by progressive flooding and eventual capsizing. CSRA supported the National Transportation Safety Board (NTSB) investigating the sinking by providing dynamic modeling and simulation of the accident voyage.

The weights, centers and inertias of this 40 year old, much modified vessel was complicated by out of date and incorrect technical drawings, minimalist CargoMax load out documentation and lack of other critical information. While the results of the analyses were adequate to support the further modeling, they were marred by having to estimate the weights and centers in a number of areas. Sensitivity studies were used to evaluate the impact of errors in the roll, pitch and yaw gyradii on the motions in hurricane seas.

}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3698/buy}, author = {Kery, Sean and Dominick Cimino and Bragulla, Paul} } @conference {3673, title = {3673. A Recommended Weight Margin Approach for Wet Undersea Vehicles}, booktitle = {76th Annual Conference, Montreal, Canada}, year = {2017}, month = {05/2017}, pages = {7}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Montreal, Canada}, abstract = {

Non-pressurized fully flooded (or {\textquotedblleft}wet{\textquotedblright}) undersea vehicles are sensitive to weight and buoyancy changes. Thus, wet vehicles as they will be referred to from here on out, need the application of both an uncertainty margin for weight and buoyancy prediction during the design development phase. Classical margin approaches for addressing risk uncertainty in surface ships or pressurized submersible vehicles do not address buoyancy uncertainty. This is primarily due to establishing and locking-in the surface ship hull or the pressure hull of a submersible vehicle early in the design. Therefore, margin approaches that address both weight and buoyancy uncertainty during wet undersea vehicle designs appear to be needed.

}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3673/buy}, author = {Boze, William} } @conference {3674, title = {3674. A Weight Analysis of Civil War Ironclad CSS Virginia}, booktitle = {76th Annual Conference, Montreal, Canada}, year = {2017}, month = {05/2017}, pages = {79}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Montreal, Canada}, abstract = {

This paper presents a weight analysis of and radius of gyration calculations for the Civil War Ironclad CSS Virginia, built by the Confederate States Navy to attempt a break of the Union Blockade of Hampton Roads in Southeastern Virginia in 1862. The weight analysis was done in conjunction with a larger naval architecture analysis accomplished as a master{\textquoteright}s thesis for an MS in Ocean Engineering from Virginia Tech. This paper specifically reports the weight and radius of gyration analyses, and notes some of the conclusions that can be made based on the ship{\textquoteright}s weights, basic hydrostatic properties, and estimated center of gravity.

The paper begins with a brief overview of the history behind the CSS Virginia, including the development of ironclad vessels up to 1862. The service life of the Virginia is briefly discussed to lend the weight analysis context.

The paper then discusses the weight analysis and radii of gyration calculations in detail. The weight analysis utilized a geometry model of the Virginia made using Paramarine software, as well as historical information in the form of model plans, books, articles, and other sources. Microsoft Excel was used to track the weights for the estimate, and a variety of methodologies were used to estimate different aspects of the ship{\textquoteright}s weight and center of gravity. The different items examined included but were not limited to:

* Ship{\textquoteright}s structure (the hull, decks, iron armor, etc.)
* Armaments and ammunition
* Provisions
* Weight of personnel serving on board and their effects
* Propulsion machinery weights

The weight estimate was used to develop radii of gyration calculations based on weight distributions per SAWE RP-17, Weight Distribution and Moments of Inertia for Marine Vehicles.

In the thesis (Marickovich, 2016), the information from the weight estimate was taken as an input for a larger naval architecture analysis of the CSS Virginia, particularly in regards to seakeeping. The results of the weight estimate are presented here, as are results from the analysis pertaining to initial stability (which is largely dependent on the ship{\textquoteright}s vertical center of gravity). The overall results of the seakeeping analysis are very briefly mentioned, as well as a hypothesis questioning certain aspects of the history surrounding the Virginia{\textquoteright}s destruction which is based on the ship{\textquoteright}s hydrostatics. Readers interested in the broader naval architecture analysis should consult the full thesis, which is available through Virginia Tech{\textquoteright}s ETD database.

}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3674/buy}, author = {Marickovich, Nicholas E.} } @conference {3676, title = {3676. Weight Control: Idealistic vs. Realistic}, booktitle = {76th Annual Conference, Montreal, Canada}, year = {2017}, month = {05/2017}, pages = {14}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Montreal, Canada}, abstract = {

Often, the requirements for determining the mass properties of a ship are contractually establishedbythecustomerand/orthedesignagent. Inreallifethough,withintheshipyard, many of those requirements physically can{\textquoteright}t be done, are in themselves not accurate, or fall by thewaysideduetocostand/orschedulefactors. EveninsomeoftheRecommendedPractices, there are {\textquotedblleft}requirements{\textquotedblright} that are misconceived. This paper discusses several examples that can (and will) deter from what would be an {\textquotedblleft}idealistic{\textquotedblright} weight control program.

}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3676/buy}, author = {R. Alan Bird} } @conference {3677, title = {3677. Considerations for Reviewing Ship and Submarine Weight Reports}, booktitle = {76th Annual Conference, Montreal, Canada}, year = {2017}, month = {05/2017}, pages = {22}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Montreal, Canada}, abstract = {

Ship weight control must be practiced diligently in both the cus- tomer{\textquoteright}s and the contractor{\textquoteright}s organizations. Part of the customer{\textquoteright}s weight control process is the careful review of periodic weight reports that are produced and submitted by the contractor. The purpose of this paper is to present some considerations for the proper review of these weight reports including basic requirements, tools available to the reviewer, knowledge the review should have, the approach to the review, reviewing accepted weight reports, reviewing quarterly weight reports, common issues, schedules, and areas of concern during weight audits.

}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3677/buy}, author = {Tellet, David} } @conference {3678, title = {3678. Submarine Static Stability}, booktitle = {76th Annual Conference, Montreal, Canada}, year = {2017}, month = {05/2017}, pages = {39}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Montreal, Canada}, abstract = {

This paper complements [Tel07] and discusses basic sub- marine stability. Areas covered include submarine arrange- ments, centers of gravity and buoyancy, hydrostatics and volumetrics, the principle of the metacenter, types of stabil- ity (including surfaced, submerged, damaged, longitudinal, transitional, and under-ice), stability criteria, and a section on how to calculate stability. The appendix includes typical calculation forms and a discussion of free surface moments and how they are calculated.

}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3678/buy}, author = {Tellet, David} } @conference {3687, title = {3687. An Updated Initial Parametric Weight Equation Compendium}, booktitle = {76th Annual Conference, Montreal, Canada}, year = {2017}, month = {05/2017}, pages = {50}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Montreal, Canada}, abstract = {

When developing the initial weight estimate for a new vessel, the weight engineer or naval architect can produce his or her estimate either by scaling from a known, similar vessel, or by taking the weights of each portion of the vessel from parametric equations or by some combination of these two methods. The preferred source of a parent vessel to scale from or the data from which a parametric equation is derived is the past vessels designed by the naval architect{\textquoteright}s own firm; however, sometimes the firm may not have suitable designs in its portfolio to base a new design weight estimate upon. This paper seeks to collect as many previously published parametric weight equations for as wide a collection of vessel types as possible in order to provide a convenient reference for the times the naval architect{\textquoteright}s own data is insufficient to complete a weight estimate.

This paper is not intended to be the definitive source of parametric weight equations, rather, the goal is to collect a critical mass of equations across the range of vessel types to start the conversation on the relative merits of the various equations and hopefully elicit new up-to-date equations from others. Ideally discussers will add equations based on their own data in addition to discussing the merits of those collected here. The end goal is the production of a SNAME T\&R Bulletin, however much additional validation, updating and discussion is required to take the current paper to the point where it could be considered as a true draft for such a bulletin.

In all cases, the reader is encouraged to consult the original source and attempt independent validation before using any of the equations collected herein.

}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3687/buy}, author = {Hansch, David} } @conference {3693, title = {3693. A Random Method for Picking Module Stowage Solutions for Barges}, booktitle = {76th Annual Conference, Montreal, Canada}, year = {2017}, month = {05/2017}, pages = {15}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Montreal, Canada}, abstract = {

In the Oil \& Gas Construction Industry, many onshore projects are using modular construction. This type of construction requires that the modules be transported from the fabrication yard to the project site. The fabrication yard may be distant from the project site, thus requiring ocean transportation. Modules can come in many different sizes, shapes, and weights. Some very large modules require a dedicated barge. However, frequently multiple modules can be placed upon a single barge. Determining module groups for barges can be difficult and time consuming. Figure 1 shows several different types of modules on barges.

Determining the type of barge to use, the number needed, and the length of service time can be a daunting logistical task. Costs involved with securing barges and engineering services from barge companies are in the millions of dollars. To complicate matters, barges typically require long lead times. Determining what type of barge or the appropriate {\textquotedblleft}mix{\textquotedblright} of barges to use can help reduce the cost of the project.
This paper will demonstrate a method to easily solve for a group solution through the use of a random number generator and grading the resultant solutions. This method can easily be applied to other types of problems and industries when it is necessary to pick groups to solve the problem.

}, keywords = {13. Weight Engineering - Marine, 21. Weight Engineering - Statistical Studies, 35. Weight Engineering - Offshore}, url = {https://www.sawe.org/papers/3693/buy}, author = {Robert Hundl} } @conference {3669, title = {3669. Light Ship or Load? Uncertainty in Shipboard Weight Surveys}, booktitle = {75th Annual Conference, Denver, Colorado}, year = {2016}, month = {05/2016}, pages = {10}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Denver, Colorado}, abstract = {Adequate stability for a ship is critical to the vessel{\textquoteright}s safety and operation, the safety and well being of its crew and passengers, and its ability to accomplish its mission. To validate that a ship has acceptable stability, a detailed inventory of the ship is conducted to determine what weights must be added or deducted in order to arrive at an accurate light ship center and weight. This determination is important in arriving at the ship{\textquoteright}s true light ship weight and center, a basis for calculating the ship{\textquoteright}s draft, trim, and stability characteristics. Small vessels may only require a couple of people and a few hours to complete such a survey while a larger vessel, on the other hand, can require several thousand manhours and more than a week to perform. The accuracy of this important survey depends on the available manpower, the experience of the surveyors, the size and complexity of the ship, and, most importantly, the accuracy and consistency practiced by the people conducting the survey. Currently, there are two guidance documents: the Navy{\textquoteright}s Naval Ships Technical Manual (NSTM) Chapter 096, Weight and Stability, and the Society of Allied Weight Engineer{\textquoteright}s (SAWE) Recommended Practice M-9, Shipboard Weight Surveys. However, it has been observed that there are still many areas of inconsistency from one surveyor to the next, one type of ship to the next, one shipyard to the next, and even from one Navy observer to the next. There are also new trends observed on naval vessels that need to be factored into a ship survey such as the growing trend of increased shipboard items introduced by the ship{\textquoteright}s force to improve quality of life, increased stores, and increased equipment that may or not be a permanent fixture on the vessel. Currently, these items default to a judgment call by the individual surveyor or the organization conducting the survey. This inconsistency causes inaccuracy and reduces the value of conducting these surveys. It also reduces the value of the data to determine trends and to compare one ship to another. How much inaccuracy is inherent in this process is not known and cannot be easily measured. It is the intent of this paper to identify areas of actual or potential inaccuracy and inconsistency and offer suggestions on how to resolve them Rationale for making a decision as to whether a newly encountered item falls into the light ship or variable load category will also be offered to better enable surveyors to make a reasonable decision during a survey. Guidance will also be provided to determine into which load category new or questionable items should be placed. The main objective is to increase the accuracy of shipboard weight surveys, reduce the inaccuracy of shipboard weight data, and improve the consistency of weight surveys across multiple ship classes and across the industry.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3669/buy}, author = {Marickovich, Nicholas} } @conference {3632, title = {3632. Challenges Encountered Doing Weight Reports on Multiple Ship Contracts}, booktitle = {74th Annual Conference, Alexandria, Virginia}, year = {2015}, month = {05/2015}, pages = {13}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Alexandria, Virginia}, abstract = {Some multi-hull Contracts require that a detailed weight report be generated for only the lead ship in a class, while other contracts require detailed weight reports for each hull in the program. There are many aspects that have to be dealt with for multiple hull contracts primarily, handling hull specific contract modifications. Done incorrectly, dealing with multiple spreadsheets or databases to do weight reports can easily lead to an administrative {\textquotedblleft}nightmare{\textquotedblright} and create a great source of errors. This paper discusses an approach used to mitigate duplicate entries and potential errors. It does not go into the details of the revisions made by BAS Engineering to the ShipWeight computer program which added the Phase Code feature, but instead, explains how and why the Phase Codes are used. Proper Database Management is required to ensure consistency, and a time savings (cost) approach to developing weight reports for follow-on ships under multi-hull contracts.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3632/buy}, author = {R. Alan Bird} } @conference {3633, title = {3633. Methods Used for Tracking, Validating, and Reporting the Weight of Operating Space Items (OSI) and Storeroom Items (SRI)}, booktitle = {74th Annual Conference, Alexandria, Virginia}, year = {2015}, month = {05/2015}, pages = {19}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Alexandria, Virginia}, abstract = {Many times, items are listed as {\textquotedblleft}Items to Deduct{\textquotedblright} during the Deadweight Survey, which, according to the Expanded Ship Work Breakdown Structure (ESWBS), are actually part of Lightship. Due to misconceptions and/or errors, the Deadweight Survey is not accurate when compared to the Mass Properties Reports. The largest confusion is with the definition of Operating Space Items (OSI), Storeroom Items (SRI), and General Use Consumable List (GUCL) items. Another issue is that OSI is most often completely missed in the early stages of a weight estimate and those items are also among the most challenging to get accurate weight values for. Weighing of these items is difficult as these are generally small items and have a high risk of being pilfered or 0damaged, and are therefore not loaded out until delivery. Although arriving late in the weight estimating schedule, getting accurate weights for the {\textquotedblleft}little things{\textquotedblright} that make the ship work will benefit the Deadweight Survey / Inclining Experiment, and will also yield valuable data for future parametrically generated weight estimates. This paper shows one method used to accurately capture the weight and the locations on the ships where these items will be.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3633/buy}, author = {R. Alan Bird} } @conference {3639, title = {3639. Weights Engineering of Historic Vessels}, booktitle = {74th Annual Conference, Alexandria, Virginia}, year = {2015}, note = {

Mike Hackney Best Paper Award, 2015

}, month = {05/2015}, pages = {22}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Alexandria, Virginia}, abstract = {

Weights engineering feeds into hydrostatic trim and stability analysis and hydrodynamic analyses of many sorts. It is an important task that requires attention to detail and hours spent carefully reviewing drawings and manufacturers cut sheets to develop data at the necessary level of detail. What do you do when the ship was built far in the past and few or no drawings exist? What if there are a few drawings and references but they conflict on critical details? Will we ever be able to do an adequate weights analysis? This paper describes several such analyses and the detective work and re-engineering that has gone into developing reasonable weights and centers information for these historic vessels. These analyses were used to support sinking analyses in several cases and the problem is significantly different for a wooden vessel than a iron or steel vessel. The just-submerged analysis is significantly different from the surface analysis. Many tricks of geometry and integrating the results from different software can be used to further the understanding of the missing data.

}, keywords = {13. Weight Engineering - Marine, Mike Hackney Best Paper Award}, url = {https://www.sawe.org/papers/3639/buy}, author = {Kery, S} } @conference {3646, title = {3646. Improvements and Guidance to the Weight Classification Using Expanded Ship Work Breakdown Structure (ESWBS)}, booktitle = {74th Annual Conference, Alexandria, Virginia}, year = {2015}, month = {05/2015}, pages = {63}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Alexandria, Virginia}, abstract = {This paper presents a guide to identify the proper classification of weight data for USN ships using the Navy{\textquoteright}s current Expanded Ship Work Breakdown Structure (ESWBS) system. ESWBS is a functional classification system that is used for weight reporting purposes. It is used on all USN ships as well as many other shipbuilding programs as a method by which all weight estimates are functionally organized. Also, ESWBS is used as an aid to developing ship cost estimates. With the introduction of newer technologies, materials and constructions practices in ship designs, the proper weight accounting has become more difficult and somewhat subjective. Therefore, this paper provides guidance and clarification on the proper weight classification of elements in a weight estimate with a focus on the newer technologies and practices.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3646/buy}, author = {Garzke, W and Dominick Cimino and Yoder, M} } @conference {3610, title = {3610. Inertia Uncertainity of a Moored FPSO}, booktitle = {73rd Annual Conference, Long Beach, California}, year = {2014}, month = {05/2014}, pages = {13}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Long Beach, California}, abstract = {This paper will address weight requirements t o ensure the delivered mass inertia properties match the initial estimates used for model testing and hydrodynamic performance assessment. It has been assumed that the large dead weight of an FPSO makes the design insensitive to variances in mass inertia over the design cycle. As hydrodynamic engineers improve their mooring design performance and reduce margins, minor changes in mass inertia can have dramatic impact on system response. This paper will compare the mass inertia estimating, uncertainty and detailed calculation with mooring performance to determine optimum thresholds for weight control to mitigate the risk of changes in inertia.}, keywords = {06. Inertia Measurements, 13. Weight Engineering - Marine, 35. Weight Engineering - Offshore}, url = {https://www.sawe.org/papers/3610/buy}, author = {Chandrasekaran, Santhosh Kumar and Schuster, Andreas} } @conference {3611, title = {3611. Differences between Marine and Offshore Weight Control}, booktitle = {73rd Annual Conference, Long Beach, California}, year = {2014}, month = {05/2014}, pages = {8}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Long Beach, California}, abstract = {The Marine and Offshore industries are closely related because both systems must with stand ocean forces to continue to operate. Weight Control for both systems is similar, but then again different. This paper will outline some of the differences in perspective, business models, technical issues and processes. The paper is intended to compliment the {\textquotedblleft}Principals of Weight Management and Weight Estimating for the Offshore Oil Industry{\textquotedblright} SAWE training class and to make the Marine community within SAWE aware of the Offshore issues, so two communities can share standards.}, keywords = {13. Weight Engineering - Marine, 35. Weight Engineering - Offshore}, url = {https://www.sawe.org/papers/3611/buy}, author = {Schuster, Andreas} } @conference {3617, title = {3617. In-Service Weight Control for Submarines}, booktitle = {73rd Annual Conference, Long Beach, California}, year = {2014}, month = {05/2014}, pages = {23}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Long Beach, California}, abstract = {Weight control for submarines must continue throughout the service life to ensure proper ballasting, operational readiness, and ship safety. This paper describes the reasons for in-service weight control, some capa- bilities and constraints, known and unknown weight change calculations, the tools used to measure submarine weight and volume, and the roles and responsibilities of the organizations that are involved with the fleet. The process of developing a ship alteration is discussed and a timeline of a typical submarine major availability is displayed and described. The requirements and reasons for reporting and approvals is also discussed.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3617/buy}, author = {Tellet, David} } @conference {3568, title = {3568. Weight Reporting on the Cheap}, booktitle = {72nd Annual Conference, St. Louis, Missouri}, year = {2013}, month = {05/2013}, pages = {23}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Saint Louis, Missouri}, abstract = {The methods and processes to produce quality weight reports range from large legacy mainframe systems to laptop spreadsheets. This paper presents an alternate method of producing weight reports that combines proper database controls with flexible document generation. These reports also provide additional information such as weight trends across periodic weight reports and graphical representation of the position of the centers of gravity in relation to the ship. The weight reporting method presented is based on open source software and is flexible, portable, and affordable to develop and maintain.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3568/buy}, author = {Tellet, David} } @conference {3569, title = {3569. Revisiting Seawater Density and its Impact on Submarine Design}, booktitle = {72nd Annual Conference, St. Louis, Missouri}, year = {2013}, note = {

Mike Hackney Best Paper Award

}, month = {05/2013}, pages = {88}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Saint Louis, Missouri}, abstract = {

This paper presents an analysis of seawater density data and relates the findings to submarine design impacts. Oceanographic temperature, depth, and salinity data from all the Earth{\textquoteright}s oceans and seas were analyzed to test the hypothesis that the standard heavy density value used by the US Navy could be reduced for certain submarine designs. The data support the hypothesis. Design impacts of reducing water density requirement are noted. The paper includes a summary table of all the data and detailed summary sheets for each of the 100 separate datasets used in the analysis.

}, keywords = {13. Weight Engineering - Marine, Mike Hackney Best Paper Award}, url = {https://www.sawe.org/papers/3569/buy}, author = {Tellet, David} } @conference {3601, title = {3601. Guidelines for Submarine Weight Moment of Inertia Calculations}, booktitle = {72nd Annual Conference, St. Louis, Missouri}, year = {2013}, month = {05/2013}, pages = {11}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Saint Louis, Missouri}, abstract = {Traditionally the roll weight moment of inertia and gyradius for sub- marines have been estimated values. This paper discusses the weight moment of inertia calculation, the proper way to handle structure that is symmetric about the roll axis, and provides guidelines for calculation methods, reporting requirements, and the optimum percentage of the to- tal weight that should be used for the self inertia calculations. The paper includes a method to include acquisition and service life margins in the inertia calculations.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3601/buy}, author = {Tellet, David} } @conference {3604, title = {3604. Offshore Wind Turbine Design and the Importance Of Weight Management in Guiding Design}, booktitle = {72nd Annual Conference, St. Louis, Missouri}, year = {2013}, month = {05/2013}, pages = {16}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Saint Louis, Missouri}, abstract = {The offshore wind turbine industry has been moving at a very high pace towards ever deeper waters and larger generators. Foundation and installation costs are a significant portion of total costs. Installation vessel designs have struggled to keep pace with the advance of turbine designs, increasing water depth, and innovative installation concepts. The increasing turbine size and water depth is driving the cost of these vessels ever higher. This is driving wind farm project costs beyond economic viability. Examining the effect of transportation and installation methods, this paper identifies the value in a strong integration between turbine design and installation methods for optimum economic viability.}, keywords = {13. Weight Engineering - Marine, 35. Weight Engineering - Offshore}, url = {https://www.sawe.org/papers/3604/buy}, author = {John R. Capin} } @conference {3605, title = {3605. The Weight Estimate: Tim Nolan Marine Design{\textquoteright}s Weight Estimate Procedures}, booktitle = {72nd Annual Conference, St. Louis, Missouri}, year = {2013}, month = {05/2013}, pages = {58}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Saint Louis, Missouri}, abstract = {The following report: The Weight Estimate: Tim Nolan Marine Design{\textquoteright}s Weight Estimate Procedures, is a description of the weight estimate process from start to finish at Tim Nolan Marine Design. This report provides a detailed description of both the empirical and itemized weight estimates as well as an explanation of the relationship between Tim Nolan Marine Design and the shipyard during construction. After the weight process is thoroughly explained, an analysis and recommendations of the overall method are given. Finally a proposal to create an accurate weight estimate for the Rushmore Project is offered. In this proposal the suggestions outlined are to (1) create a detailed weight estimate spreadsheet, (2) keep all weight estimate documentation up to date, (3) request machinery and wiring weight information from the shipyard, (4) request the shipyard weigh the vessel frequently throughout the construction process, and (5) create a relationship with the interior design team to create accurate joinery weight estimates.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3605/buy}, author = {Nicole Sanderson} } @conference {3592, title = {3592. A Background in Offshore Floating Production Unit Weight Control Nomenclature and a Proposal for Future Development}, booktitle = {71st Annual Conference, Bad G{\"o}gging, Germany}, year = {2012}, month = {05/2012}, pages = {9}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Bad G{\"o}gging, Germany}, abstract = {In estimating and managing weight growth during concept, design and fabrication phases for offshore energy floating production platforms and vessels, two similar but different methodologies for representing weight nomenclature have arisen thus leading to confusion and turmoil within the weight control discipline. This paper delves into the background and origins of these weight control methodologies and seeks to open the discussion on the differing nomenclatures found within the weight control function. This will be done by giving some examples of weight control terminology with multiple definitions and proposing a new concept of weight nomenclature based on the stages and states of weight development.}, keywords = {13. Weight Engineering - Marine, 17. Weight Engineering - Procedures, 35. Weight Engineering - Offshore}, url = {https://www.sawe.org/papers/3592/buy}, author = {Zawadzki, Radoslaw} } @conference {3527, title = {3527. Submarine Asymmetric Margin Selection}, booktitle = {70th Annual Conference, Houstion, Texas}, year = {2011}, month = {05/2011}, pages = {52}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Houston, Texas}, abstract = {This paper presents methods and results of a study to determine appropriate early-stage design margins for a submarine design. The submarine design is unique in that the center section design is more mature than the rest of the boat. Because of this a simulation was created to study the margin usage during early stage design, through design and construction, and up to delivery. The simulation provided data to support the selection of separate center section and whole boat margins based on certainty levels and optimistic, neutral, and pessimistic outlooks. The results of the study show that margin usage correlates highly with initial margin values, that variations of the initial center section margin affect the remaining margin less than the initial boat margin, and that the initial margin goals may have been set higher than necessary. The paper concludes with recommendations for initial margin amounts.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3527/buy}, author = {Tellet, David} } @conference {3529, title = {3529. An Approach towards Estimating and Validating Ship Stowage and Stowage Content Weight}, booktitle = {70th Annual Conference, Houstion, Texas}, year = {2011}, month = {05/2011}, pages = {15}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Houston, Texas}, abstract = {In every ship design weight engineers are challenged with estimating the weight and center of gravity for stowage aides and stowage contents particularly in the pre-contract stage of ship design. Ratiocination techniques using parent hull designs contained in SAWE Weight Engineers Handbook (SAWE, 1986) will suffice at the concept phase of design, but as the design progresses a weight engineer requires higher fidelity information for storeroom location and function, types and number of stowage aids within a storeroom, as well as the number of lockers and special stowage aids scattered throughout the ship. Hull outfitting design and construction products for stowage aids are typically scheduled for issue after primary hull structure and major through services and equipment arrangements have been established. Also, the list of items to stow is not provided until very late in the design. As a result this portion of the reported ship weight and center is usually neglected by the weight engineer due to the perceived lack of information and realization that {\textquotedblleft}stowage{\textquotedblright} accounts for only approximately one percent of the lightship weight and one percent of the load weight. Yet, most weight engineers are unaware of an abundance of information available mainly due to their lack of knowledge in the ship design and storeroom and stowage aid design process. This paper in meant to enlighten the marine weight engineer in a process used successfully for evolving the estimates and calculations for stowage aid and contents weight and center of gravity from the early to latter phases of ship design.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3529/buy}, author = {Boze, William} } @conference {3534, title = {3534. Mass Properties Requirements For Marine Design Software}, booktitle = {70th Annual Conference, Houstion, Texas}, year = {2011}, month = {05/2011}, pages = {18}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Houston, Texas}, abstract = {Design tools have made significant progress since the days of drafting boards and T-squares. Today{\textquoteright}s advanced 3-D product modeling systems offer tremendous capability in both design and analysis. However, the same capabilities that benefit the ship designer are usually not optimized for the mass properties engineer or weight calculator who must extract data from the product model to determine weights and moments for the marine product in question. In the marine field, the identification of functionality to support the mass properties function is developed each time a new design system is deployed and often gets much less attention than the design function. Because new design tools are usually not developed specifically for the marine industry, extensive customization including mass properties functionality is generally required for each marine application. No industry standard exists for the basic functional requirements which a new design tool should satisfy. This paper will attempt to define core functional requirements needed by mass properties engineers in the marine field. It is hoped that this effort will allow the mass properties engineer faced with the advent of a new design tool to dedicate more time in the future to the unique or specialized features desired rather than the core mass properties requirements that should be met by all advanced design tools.}, keywords = {12. Weight Engineering - Computer Applications, 13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3534/buy}, author = {Titcomb, Alan and Carter, Keith and Moore, Ronnie} } @conference {3501, title = {3501. Simulation-based Transitional Stability Criteria for Submarines}, booktitle = {69th Annual Conference, Virginia Beach, Virginia}, year = {2010}, note = {

Mike Hackney Best Paper Award

}, month = {05/2010}, pages = {54}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Virginia Beach, Virginia}, abstract = {

This paper documents the analysis of simulation-based submarine roll data pursuant to the development of new submarine stability criteria for the transition between submerged and surfaced conditions. A matrix of ship, environmental, and simulator conditions was developed resulting in 137 different run conditions, each of which was repeated 50 times for a period of 200 seconds at a sample rate of 1Hz. This resulted in 6850 data files and 1.37 million data points for each of the seventeen channels of data recorded (e.g., speed, depth, roll, pitch). The data was processed semi-automatically through a custom document process program designed by the author using the R statistical environment for statistical analysis and data graphics, and LATEX for typesetting detailed and summary reports for each condition and each run. This paper looks at roll angles only, and mainly for the most extreme 34 of the 137 conditions used in the simulation matrix (six conditions in lower sea states were also included). In Part I the effects of varying BG, inertia, depth and speed, wind, wave height, wave direction, phase, and sail configuration are analyzed in condition to condition comparisons. Part II proposes new transitional stability criteria based on traditional static stability calculations and also on dynamic roll probabilities based on the results of Part I. The static criteria is based on a minimum GM of 0.15 feet, minimum levels and times for stability restitution, and energy comparison. The dynamic criteria is based on the probabilities of exceeding 30, 45, and 60\ roll angles in beam seas corresponding to sea states 6, 7, and 8.

}, keywords = {13. Weight Engineering - Marine, Mike Hackney Best Paper Award}, url = {https://www.sawe.org/papers/3501/buy}, author = {Tellet, David} } @conference {3504, title = {3504. Method for Finding Min and Max Values of Error Range for Calculation of Moment of Inertia}, booktitle = {69th Annual Conference, Virginia Beach, Virginia}, year = {2010}, month = {05/2010}, pages = {26}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Virginia Beach, Virginia}, abstract = {Modern ship design practices require knowledge of a vessel s mass Moment of Inertia (MOI) for various aspects of performance analysis. To find an accurate MOI value of an object, one needs to know the object s actual shape and density to be able to calculate the MOI through integration. Determining the exact MOI for a complete vessel, comprised of thousands of items, is not practical. Instead, engineers simplify the parts of the vessel to point objects or to standard shapes like a box or a cylinder, and calculate an approximation of the MOI. The accuracy of this approximation is dependent on the number of parts the vessel is divided into and how well the shape, orientation and density of each of the simplified items resembles the real objects. The quantification of the inaccuracy involved is seldom addressed. This paper describes a method to find the absolute error range for this simplified MOI calculation by finding the extreme values the MOI approximation can generate, and quantifies the effect that an error in MOI can have on the results of various types of performance analysis.}, keywords = {05. Inertia Calculations, 13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3504/buy}, author = {Aasen, Runar and Hays, Bruce} } @conference {3505, title = {3505. Early~Stage~Weight~and~Cog~Estimation~Using~Parametric Formulas~and~Regression~on~Historical~Data}, booktitle = {69th Annual Conference, Virginia Beach, Virginia}, year = {2010}, month = {05/2010}, pages = {35}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Virginia Beach, Virginia}, abstract = {Estimation~ of~ weight~ and~ center~ of~ gravity~ is~ an~ essential~ task~ in~ the~ design~ phase~ of~ a~ vessel,~ and~ the~ quality~ of~ this~ work~ will~ be~ crucial~ for~ the~ success~ of~ the~ project.~ It~ is~ important~ to~ have~ the~ best~ possible~ estimate~ for~ total~ lightship~ weight,~ but~ when~ it~ comes~ to~ construction~ and~ installation~ there~ will~ be~ a~ demand~ for~ detailed~ budgets.~ A~ certain~ detail~ level~ for~ the~ weight~ budget~ will~ also~ make~ it~ easier~ to~ find~ the~reasons~for~any~deviations~that~may~occur~during~the~monitoring~phase.~ The~ use~ of~ parametric~ estimation~ based~ on~ several~ reference~ ships~ and~ regression~ lines~ has~ traditionally~ been~ characterized~ as~ too~ demanding,~ because~ of~ time~ demands~ as~ well~ as~ complexity.~ This~ article~ will~ describe~ some~ assumptions~ and~ methods~ that~ make~ it~ possible~ and~ preferable~ to~ use~ parametric~ estimation~ on~ a~ regular~ basis~ when~ designing~ and~ building~ a~ ship,~ either~ by~ the~ use~ of~ built-in~ formulas~ and~ graphs~ found~ in~ spreadsheets,~ or~ by~ the~ use~ of~ database~ related~ weight~ control~ systems~ like~ ShipWeight.~ This~ article~ will~ discuss~ topics~ like~ breakdown~ structures,~ methods,~ selection~ of~ coefficients,~ selection~ of~ detail~ level,~ reporting~ and~ exporting~ of~ results,~ together~ with~ design~ changes~ and~ re- estimation.}, keywords = {13. Weight Engineering - Marine, 21. Weight Engineering - Statistical Studies}, url = {https://www.sawe.org/papers/3505/buy}, author = {Aasen, Runar and BJORHOVDE, STEIN} } @conference {3511, title = {3511. The Use of Inferential Statistics in Ships{\textquoteright} Stability Analysis}, booktitle = {69th Annual Conference, Virginia Beach, Virginia}, year = {2010}, month = {05/2010}, pages = {17}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, address = {Virginia Beach, Virginia}, abstract = { A deterministic approach is traditionally performed for damage stability analysis on Navy ships, while commercial, ABS accredited, ships use Safety of Life At Sea (SOLAS) and International Maritime Organization (IMO) probability studies. SOLAS and IMO analyses provide an attained subdivision index, but do not allow the designer to determine the actual KG value required to survive damage a certain percentage of the time. In a deterministic approach one would have to analyze all cases to determine the passing percentage. The use of inferential statistics will allow one to determine the KG required for a ship to survive damage a certain percentage of time, or the percentage of cases that will meet the analyzed stability criteria at a particular KG, without having to analyze every damage case, and provides more detail than an attained subdivision index, as with SOLAS and IMO requirements.}, keywords = {13. Weight Engineering - Marine, 21. Weight Engineering - Statistical Studies}, url = {https://www.sawe.org/papers/3511/buy}, author = {COOLEY, MELISSA and DIGGS, MICHAEL and Hansch, David} } @conference {3477, title = {3477. The Health of Mass Properties Engineering in the Marine Industries}, booktitle = {68th Annual Conference, Wichita, Kansas}, year = {2009}, month = {5/16/2009}, pages = {58}, type = {13. Weight Engineering - Marine ; 21. Weight Engineering - Statistical Studies ; 30. Miscellaneous}, address = {Wichita, Kansas}, abstract = {

A survey on the health of mass properties engineering in the marine field was conducted using the Internet to gather demographic, job satisfaction, industry health, and SAWE specific data. The survey consisted of 20 multiple choice, ranking, and fill-in\ questions. This paper presents the summary of the data received (139 respondents) for each question and examines some correlations between age, employers, expected attrition, and membership in the SAWE. Selected narrative answers are shown in the body of the paper with all text responses included in the Appendix.

}, keywords = {13. Weight Engineering - Marine, 21. Weight Engineering - Statistical Studies, 30. Miscellaneous}, url = {https://www.sawe.org/papers/3477/buy}, author = {Tellet, David} } @conference {3478, title = {3478. Weight Report Sanity Checks using Information Graphics}, booktitle = {68th Annual Conference, Wichita, Kansas}, year = {2009}, month = {5/16/2009}, pages = {23}, type = {13. Weight Engineering - Marine ; 21. Weight Engineering - Statistical Studies }, address = {Wichita, Kansas}, abstract = {

This paper presents methods of performing {\textquotedblleft}sanity checks{\textquotedblright} on weight reports using un-traditional information graphics. The paper discusses using bubble plots and treemaps to look at three digit weights by group and three digit weights by weight maturity levels. Comparisons of pie charts with dotcharts are discussed along with other statistical graphics such as triangle plots, stars plots, and sparklines, all of which can be used to identify potential problem areas and can be used to compare one quarterly weight report with another. The use of animated graphics is briefly discussed with regard to quickly identifying trends.

}, keywords = {13. Weight Engineering - Marine, 21. Weight Engineering - Statistical Studies}, url = {https://www.sawe.org/papers/3478/buy}, author = {Tellet, David} } @conference {3453, title = {3453. Modernizing Inclining Experiment Tools and Methods}, booktitle = {67th Annual Conference, Seattle, Washington}, year = {2008}, month = {5/19/2008}, pages = {14}, type = {13. Weight Engineering - Marine; 17. Weight Engineering - Procedures}, address = {Seattle, Washington}, abstract = {

The purpose of this paper is to propose new, more modern tools and methods for performing an inclining experiment on ships and submarines. The paper describes the process of an inclining experiment and the current tools and methods used. New tools are proposed and described for the weight survey and inventory of load items, determining the density of liquid load items, and measuring the density of the water in which the ship is floating. Reading draft marks and weighing inclining weights is discussed briefly. The move to electronic range finders and inclinometers is discussed and examples of each are shown. A discussion of error analysis follows; this is missing in the current inclining experiment reports and requirements. Finally a common inclining experiment computer application is discussed and an information display mockup shown.

}, keywords = {13. Weight Engineering - Marine, 17. Weight Engineering - Procedures}, url = {https://www.sawe.org/papers/3453/buy}, author = {Tellet, David} } @conference {3454, title = {3454. Submarine Trim Dive Weight Growth}, booktitle = {67th Annual Conference, Seattle, Washington}, year = {2008}, month = {5/19/2008}, pages = {15}, type = {13. Weight Engineering - Marine; 26. Weight Growth}, address = {Seattle, Washington}, abstract = {

This paper examines recent data from SSN 688 Class submarine trim dives that were accomplished prior to and after ma jor overhauls. The trim dives are used to determine unaccounted-for weight change prior to and during the overhaul and to verify that the submarines are properly ballasted coming out of the overhaul. The data show that there is a trend toward negative UWC in both incoming and outgoing trim dives (though this may be due to outliers) and that in both cases the range of UWC is greater than the variable ballast system can absorb. There doesn{\textquoteright}t appear to be a pattern of weight growth by shipyard. The magnitude of excess outfit values used has increased in the past few years. The outgoing UWC appears to be influenced more by the experimental error of the trim dive than by the excess outfit value used in the reballasting calculations. However, there is a correlation between the outgoing UWC and the excess outfit values used; using a value of -10 to -20 tons appears to reduce the risk of large UWC from the outgoing trim dive.

}, keywords = {13. Weight Engineering - Marine, 26. Weight Growth}, url = {https://www.sawe.org/papers/3454/buy}, author = {Tellet, David} } @conference {3455, title = {3455. Submarine Lead and Margin Attrition}, booktitle = {67th Annual Conference, Seattle, Washington}, year = {2008}, month = {5/19/2008}, pages = {26}, type = {13. Weight Engineering - Marine; 21. Weight Engineering - Statistical Studies}, address = {Seattle, Washington}, abstract = {

The selection of service life margins for a submarine has a direct impact on the design and on acquisition and operational costs because this margin is carried as actual lead ballast. Past studies carried out by NAVSEA have attempted to use lead attrition and margin lead attrition data from previous submarine classes to determine optimum ranges for service life margin. This paper documents and updates the data used in those studies and examines the data in terms of means, standard deviations, and confidence bounds around linearly fitted models of the data. The differences among the submarine classes is noted and an attempt is made to improve the fitted models by the removal of outliers. Based on the historical data and the analysis in the paper, a recommended range for service life margin for conventional attack submarines is given to be between 2.00\% and 3.25\% of light ship weight.

}, keywords = {13. Weight Engineering - Marine, 21. Weight Engineering - Statistical Studies}, url = {https://www.sawe.org/papers/3455/buy}, author = {Tellet, David} } @conference {3458, title = {3458. Methods of Determining the Longitudinal Weight Distribution of a Ship}, booktitle = {67th Annual Conference, Seattle, Washington}, year = {2008}, month = {5/19/2008}, pages = {24}, type = {13. Weight Engineering - Marine; 17. Weight Engineering Procedures}, address = {Seattle, Washington}, abstract = {Approximation methods for weight distribution of ships are surveyed. Grouping methods such as the {\textquotedblleft}Bucket{\textquotedblright} and station method are also explored. Detail based methods are explained. Finally, an improved method of distribution based on details is proposed. Guidance for the requirements of a weight database for this method is given and an alternative summary method is suggested to overcome difficulties caused by failure to meet certain database requirements of the detail method. Extensive appendices provide necessary figures and equations for using these methods.}, keywords = {13. Weight Engineering - Marine, 17. Weight Engineering - Procedures}, url = {https://www.sawe.org/papers/3458/buy}, author = {Hansch, David Laurence} } @conference {3398, title = {3398. Submarine Margin Determination by Stochastic Simulation}, booktitle = {66th Annual Conference, Madrid, Spain}, year = {2007}, month = {5/28/2007}, pages = {15}, publisher = {Society of Allied Weight Engineers}, organization = {Society of Allied Weight Engineers}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Madrid, Spain}, abstract = {Currently, the determination of appropriate submarine acquisition and future growth margins is based on previous successful designs. For the most part, this has ensured that recent submarine classes have delivered with the required future growth capability. However, this method does not optimize margin amounts. This paper presents an alternate method of determining margin amounts through the use of a stochastic simulation of the entire life of a submarine: from detail design and construction to delivery, to short availabilities, to overhauls, and finally to decommissioning. By modeling acquisition margin usage and known and unknown weight and KG growth as probability distributions (based on actual submarine data), the simulation can provide a probability distribution and certainty values for remaining margin at any point in the submarine{\textquoteright}s life. Developing acceptable levels of risk for margins for the latter part of the submarine{\textquoteright}s life will allow the weight engineer to go back and calculate initial acquisition and future growth margins that will be close to optimal for those risk levels. This paper addresses the proposed process, the simulation tool, and some preliminary results, but does not present actual final margin findings or recommendations. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3398/buy}, author = {Tellet, David} } @conference {3399, title = {3399. Weight Distribution Method of Determining Gyradii of Ships}, booktitle = {66th Annual Conference, Madrid, Spain}, year = {2007}, month = {5/28/2007}, pages = {21}, publisher = {Society of Allied Weight Engineers}, organization = {Society of Allied Weight Engineers}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Madrid, Spain}, abstract = {A new method of calculating the radii of gyration of a ship via numerical integration of the weight distribution is proposed. This new method eliminates the need for shape factors or actual individual moments of inertia to be entered with each data entry. Additionally, this method avoids many of the potential pitfalls associated with the traditional weight times distance squared method that occur as a design matures or legacy data is used in a modified repeat ship class. Furthermore, a method of approximating the weight distribution of a ship from a Work Breakdown Structure (WBS) based weight estimate is presented. Sample calculations showing the validity of the weight distributions and radii of gyration are included. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3399/buy}, author = {Hansch, David} } @conference {3402, title = {3402. Ship Inclining Experiment Accessory Kit}, booktitle = {66th Annual Conference, Madrid, Spain}, year = {2007}, month = {5/28/2007}, pages = {15}, publisher = {Society of Allied Weight Engineers}, organization = {Society of Allied Weight Engineers}, type = {9. WEIGHING EQUIPMENT; 13. WEIGHT ENGINEERING - MARINE}, address = {Madrid, Spain}, abstract = {US Military aircraft weighing standards specify the use of an accessory kit that includes tools similar to those used by weight engineers and naval architects for ship inclining experiments. The procurement of ship inclining experiment tools and accessories is currently a rather tedious, word of mouth process. This paper describes the typical contents of an aircraft weighing accessory kit. It then describes the ship inclining experiment and lists the tools used during the inclining process. From this, a specification and list for a ship inclining accessory kit is proposed. Hopefully, this paper will provide insight to equipment suppliers to enable them to create a Ship Inclining Experiment Accessory Kit for the marine industry.}, keywords = {09. Weighing Equipment, 13. Weight Engineering - Marine, 35. Weight Engineering - Offshore}, url = {https://www.sawe.org/papers/3402/buy}, author = {Schuster, Andreas and Oole, Thomas and Fox, William} } @conference {3420, title = {3420. Submarine Equilibrium. Where Weight and Volume Meet}, booktitle = {66th Annual Conference, Madrid, Spain}, year = {2007}, month = {5/28/2007}, pages = {17}, publisher = {Society of Allied Weight Engineers}, organization = {Society of Allied Weight Engineers}, type = {13. Weight Engineering - Marine}, address = {Madrid, Spain}, abstract = {Unlike many other vehicles where often only some upper weight limit is mandated, a submarine must always seek an equilibrium point between her weight and her buoyancy or volume. This requirement produces unique challenges to the submarine weight engineer and designer during submarine design and construction as well as during the boat?s operational life. This paper presents the fundamentals of submarine equilibrium from Archimedes to today?s submarine operations. Factors that affect equilibrium are discussed including the ocean environment, submarine weights, volume, hydrostatics, and internal arrangement. Fixed ballast and variable ballast are defined and discussed in terms of growth margin and ship operation. Finally, the method of measuring and tracking equilibrium?the equilibrium polygon?is presented, including how the polygon is constructed and how it changes when the submarine weight is changed.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3420/buy}, author = {Tellet, David} } @conference {3350, title = {3350. Combining Bulb Shapes and Metric Plate Thickness With ""Standard"" Shapes and Plate Sizes To Obtain Lightweight Structure}, booktitle = {64th Annual Conference, Annapolis, Maryland}, year = {2005}, month = {5/14/05}, pages = {9}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Annapolis, Maryland}, abstract = {Think ?outside the box? for Weight Reduction candidates In many instances, unique or challenging design processes are crippled by inadvertent comments and/or close-minded opinions. How many times has it been heard, ?We?ve always done it this way? or, ?It?ll never work?? Far too often, answers to design challenges are overlooked, or simply stifled by comments similar to these. A design team must step back, regroup, and look at the problem(s) from anew. Note the word ?team?. No matter how difficult a problem, others (and possibly even less skilled) may surprisingly have the answers. Team players can help here. As a team of diversified members, they are acquainted with the design nature, and can focus on the situation knowing the desired end result. Thinking ?Outside of the Box? is a great statement that allows design creativity. Once the smoke clears from the starting of the program, it?s time to seriously focus on the end result: delivery of the product to the customer. It is here, in the beginning, when the Weight Engineer truly makes a difference. Being part of the design team from the start will enable the Weight Engineer to enlighten the other team members about the weight status, which will minimize cost/schedule effects design changes may bring. Further, the Weight Engineer can give insight from a different approach, which can aid in proper decision making bringing success to the project. It was because of this team environment that Marinette Marine was able to successfully complete the structural design for the Improved Naval Lighterage System (INLS), which is currently under construction for the United States Navy.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3350/buy}, author = {R. Alan Bird} } @conference {3351, title = {3351. Scale Weighing The Improved Navy Lighterage System Modules}, booktitle = {64th Annual Conference, Annapolis, Maryland}, year = {2005}, month = {5/14/05}, pages = {51}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Annapolis, Maryland}, abstract = {Marinette Marine is one of four shipyards owned by the Manitowoc Corporation, all of which are located on the Great Lakes in the United States. One of the contracts currently under construction at MMC is the ?Improved Navy Lighterage System? (INLS) built for the United States Navy. This program consists of a total of twenty-nine modules, of seven similar but different designs. Future options on the contract would add 270 more. These modules are roughly 80 feet [24,4m] long, 24 feet [7,3m] wide and 8 feet [2,4m] deep, and when linked together, will form a platform for deeper draft vessels to offload to a beachhead. All of the new modules are required to be scale weighed using at least a two point lifting arrangement to obtain not only the weight, but the Longitudinal Center of Gravity (LCG) about the vessels? midperpendicular. This information is critical for the deployment of the modules from prepositioning ships. Due to the variances in the designs of the different modules, the calculated weights range from 154600 Lbs. [70125 Kg] to 257600 Lbs. [116845 Kg]. In principal, weighing these units and calculating their LCG?s sounds easy. Initially, it was envisioned to utilize crane mounted ?scales?; ones the operators use to determine safe crane loading to weigh the INLS modules. In order to calculate the LCS for each module, at least a two point lifting arrangement would have to be used. Fortunately, these modules are designed to be off-loaded by larger ships, and have lift fittings incorporated in their structure. With the variety of module designs, each had to be looked at to see how they would be weighed. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3351/buy}, author = {R. Alan Bird} } @conference {3352, title = {3352. Weight Risk Using Monte Carlo Analysis For A Marine System}, booktitle = {64th Annual Conference, Annapolis, Maryland}, year = {2005}, month = {5/14/05}, pages = {18}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Annapolis, Maryland}, abstract = {This paper presents a risk assessment method that can be used to validate margin estimates. A Monte Carlo simulation is used to determine the likelihood that a mass property limit is not exceeded during the design. This method is handy for use on complex projects was the design process uncertainty is too complex to describe with a standard normal probability distribution. The paper presents a description of risk, a method that supports Monte Carlo simulation, two examples on a ship level, and how to interpret the results.}, keywords = {13. Weight Engineering - Marine, 35. Weight Engineering - Offshore}, url = {https://www.sawe.org/papers/3352/buy}, author = {Schuster, Andreas} } @conference {3367, title = {3367. Inclining Experiment Sensitivity Analysis Using Excel Simulation Tools}, booktitle = {64th Annual Conference, Annapolis, Maryland}, year = {2005}, note = {L. R. "Mike" Hackney Award}, month = {5/14/05}, pages = {30}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Annapolis, Maryland}, abstract = {The purpose of this paper is two-fold. The main reason is to illustrate how simulation tools may be applied to experimental measurement problems to better understand and quantify uncertainties of the measurement. In the sample case used here, a generic submarine inclining experiment, any single measurement or experiment is time-consuming, expensive, and logistically challenging. Multiple measurements are not feasible and therefore, up to now, any error analysis was not based on multiple experiments on one ship, but on single on multiple sister ships. Simulation tools allow us to perform a multitude of ?what-if? scenarios on that one single experiment and quantify possible errors. The secondary reason for this paper is to use the results of the simulations to show what factors in an inclining experiment are the most important to the outcome of the experiment and thus where those performing the experiment should concentrate their efforts to ensure precision and accuracy. Since these simulations were done on a generic submarine, and with nominal values for the data, the numerical results from the simulations are not directly applicable to any particular ship or submarine. However, the relative influence of the factors are deemed to be representative of an inclining experiment on a submarine of similar size and shape.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3367/buy}, author = {Tellet, David} } @conference {3368, title = {3368. Risk Analysis Methods for Submarine Ship Alterations}, booktitle = {64th Annual Conference, Annapolis, Maryland}, year = {2005}, month = {5/14/05}, pages = {30}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Annapolis, Maryland}, abstract = {This report presents a methodology for risk modeling, analysis and management for the installation of a warfighting improvement alteration on a submarine. In the first phase the state of the system is displayed and high level objectives and constraints identified. The second phase identified 66 risk areas or sub-topics under 11 main risk topics. Using the assumption that the study was from the viewpoint of an individual Naval Architect, 19 particular subtopics were chosen for further study. Methods of risk filtering and ranking were used to look at the subtopics; six areas were identified as the highest risk/consequence areas: Weight, Channel Depth, Displacement, Vertical Moment, Draft, and Engineering Support. Weight and Channel Depth were identified as the areas of greatest concern. In Phase 3, policy options were examined to mitigate the risks for Weight and Depth: 1) Cancel shipalt; 2) Lengthen the boat; 3) Reduce mission capability; 4) Dredge harbors; 5) Use titanium vice steel; and 6) Use aggressive weight control. For each policy a cost estimate was developed as well as a probability density function (PDF) of mission degradation. The PDFs were developed using the fractile method and input from experts. From the PDFs, the expected values and the conditional expected values were calculated and plotted. Policy options 3 and 4 were determined to be inferior. Option 6 was chosen as the most promising. The last phase used a multiple-objective decision tree to examine the implementation of policy Option 6. Two periods of the tree were developed and loss vectors calculated based on cost and loss of mission capability. The results indicate that early implementation of weight control will be effective in minimizing cost and capability loss, but that later implementation may not be cost effective. The object of this study was to present a methodology to assess and manage risk. The results are based upon estimates and should not be considered representative without verification of all estimates and probability functions.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3368/buy}, author = {Tellet, David} } @conference {3311, title = {3311. Weight Risk Using Uncertainty Analysis for a Marine System}, booktitle = {62nd Annual Conference, New Haven, Connecticut}, year = {2003}, month = {5/17/03}, pages = {15}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {New Haven, Connecticut}, abstract = {This paper presents a risk assessment method that can be used to validate margin estimates. An uncertainty methodology is used to determine the probability of the final weight based on the current weight estimate. This method has been used in the aerospace industry but not extensively in the marine industry. The paper presents a description of risk, the method, two examples on the system and ship level, as well as how to interpret the results.}, keywords = {13. Weight Engineering - Marine, 35. Weight Engineering - Offshore}, url = {https://www.sawe.org/papers/3311/buy}, author = {Schuster, Andreas} } @conference {3222, title = {3222. Enhanced Ship Structural Weight Estimating Methods, Using the NAVY{\textquoteright}s ASSET Early Stage Surface Ship Design Synthesis Model}, booktitle = {61st Annual Conference, Virginia Beach, Virginia, May 18-22}, year = {2002}, month = {5/18/02}, pages = {18}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Virginia Beach, Virginia}, abstract = {The Advanced Surface Ship Evaluation Tool (ASSET) is a family of interactive computer programs used by the US Navy in exploratory and feasibility design phases of naval surface ships. The primary purpose of ASSET is to perform the initial prediction of ship physical and performance characteristics based on mission requirements and to do so with sufficient fidelity that the total ship implications of subsystem level design and technology decisions are evident. Over the last 2 years significant modifications have been made to this program in the area of ship structural weight predictions. The ASSET Hull Structure Module has adapted its methodology from another naval ship structural design program called Design Program for Ship Structures (DPSS), and it has been modified to use the ship geometry from the other ASSET modules to automate some of the selection of structural components to facilitate multiple total ship iterations, typical in early stage ship design. This paper addresses the new hull structural design enhancements implemented in ASSET Version 4.6, and walks the user through the Hull Structure Module?s methodology, requirements, output and proper user interpretation.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3222/buy}, author = {McWhite and Wintersteen} } @conference {3244, title = {3244. Weight control at Ulstein Shipyard}, booktitle = {61st Annual Conference, Virginia Beach, Virginia, May 18-22}, year = {2002}, month = {5/18/02}, pages = {18}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Virginia Beach, Virginia}, abstract = {The paper describes the results from a project on weight reporting that was launched by Ulstein Shipyard and BAS engineering and funded by the Norwegian Research Council in 1999 - 2001: To improve the efficiency and value of weight reporting in a shipyard, a survey of all weight relevant information sources on the yard should be worked out. For each information source one should clarify what information is available, when the information is available and how reliable the information is. Information sources can be various 3D tools, key persons in the constructing organization and weight information from external sources, etc. Furthermore one should specify method, format and intervals of transaction of the information from all the sources to on single weight system (Ship Weight), which will execute the total weight control and produce the weight reports (example of a weight report will be supplied). In addition to the technical procedures that were established, some reporting principles were made. The principles were implemented to all involved in the weight reporting. Some examples of the most important would be; how margins should be treated, how to treat wet/dry weights, establishing weight budgets and the principle of 100\% weight reporting. Experience from the shipyard after implementing the weight reporting routines will be discussed.}, keywords = {13. Weight Engineering - Marine, 35. Weight Engineering - Offshore}, url = {https://www.sawe.org/papers/3244/buy}, author = {Aasen, Runar} } @conference {3252, title = {3252. Developing Carbon Foam for Ship Structures}, booktitle = {61st Annual Conference, Virginia Beach, Virginia, May 18-22}, year = {2002}, month = {5/18/02}, pages = {13}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Virginia Beach, Virginia}, abstract = {The U.S. Navy is striving to find ways to build more ships for the same dollar and at the same time improve performance. This requires lower ship acquisition and life cycle costs. To achieve these goals, the Navy and its shipbuilders have implemented various initiatives, many under the domain of ?Lean Manufacturing.? The goals are to lower Navy ship acquisition and life cycles costs and improve American shipyards? ability to compete internationally. Under this domain the Navy has identified the need for new technology and manufacturing/installation methods. Touchstone Research has developed a new price competitive material, carbon foam, which is a possible replacement for current and future applications baselining steel, aluminum, nomex honeycomb, balsa wood and graphite epoxy materials. The material has unique weight, mechanical, electrical, fire resistance and protection, and acoustic properties. Potential applications include bulkheads; fire protection in high risk engine compartments, aircraft and ammunitions storage areas, top-side radar absorption, EMI shielding, ship stacks, blast deflectors. The paper describes the current carbon foam development activities for ship structures and other industries.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3252/buy}, author = {Mike Brown and Roger Crane} } @conference {3253, title = {3253. Intumescent Coatings: a Lighter Weight Way to Improve the Fire Resistance of {\textquoteright}FIBROUS{\textquoteright} Structural Bulkhead Insulation}, booktitle = {61st Annual Conference, Virginia Beach, Virginia, May 18-22}, year = {2002}, month = {5/18/02}, pages = {11}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Virginia Beach, Virginia}, abstract = {Structural insulations are used on marine bulkheads and decks to keep the fire in one compartment from spreading to an adjacent space. An intumescent coating placed on the outside of fibrous insulation will significantly reduce the quantity and weight of insulation required when compared to uncoated insulation. The coating is effective when the fire exposure is the standard time-temperature curve and the more severe hydrocarbon time-temperature curve.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3253/buy}, author = {Chandler and Gottfried} } @conference {3000, title = {3000. Weight Estimating and Reporting for Major Ship Conversions}, booktitle = {59th Annual Conference, St. Louis, Missouri, June 5-7}, year = {2000}, month = {6/5/00}, pages = {15}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {St. Louis, Missouri}, abstract = {There have been several major conversions conducted in the United States during the last decade to increase the Military Sealift Command fleet. Weight estimating and reporting for major ship conversions presents a significant challenge to the weight engineer. A major conversion is usually defined as one that changes a ship{\textquoteright}s principal dimensions, type of service, or light ship weight by 10\% or more. As-built weight data and drawings are sometimes unavailable and often the ship has already undergone many other alterations since its construction that may significantly affect weights and centers of gravity. The accurate prediction of light ship weight and centers is critical to the success of a major ship conversion since the principal characteristics (length, beam, depth, draft, speed, etc.) usually cannot be easily changed, as they can in preliminary design for new construction. This paper describes the process of preparing and maintaining weight estimates and reports throughout a major ship conversion project. Definitions and reasons for major conversions are discussed in the introduction and then the process of establishing a preconversion baseline is described. The preliminary and contract design weight estimates are described and removals, installations, vendor data, margins, level of detail, and other aspects of them are discussed. The process is then followed through the detail design and completion phases, and concluded at the post-conversion inclining. Several recent examples from the authors{\textquoteright} experience are described in detail, and lessons learned are shared with the reader. The result is a comprehensive guide to the subject that should be useful to anyone involved in ship conversion weight work.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3000/buy}, author = {Fox, W A and McMullen, J J and Gelfenbaum, C J} } @conference {3015, title = {3015. A Methodology for Selecting Naval Ship Acquisition Margins}, booktitle = {59th Annual Conference, St. Louis, Missouri, June 5-7}, year = {2000}, month = {6/5/00}, pages = {13}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {St. Louis, Missouri}, abstract = {Acquisition margins are included in a weight estimate to account for unknown or unanticipated growth in weight or KG which occur in future design phases. Weight and KG growth occurs for a variety of reasons during the course of a design. Some of these reasons are the following: 1. Errors carried over from previous design phases; 2. Requirement changes which result in equipment/system changes; 3. Ship arrangement/configuration changes; 4. Increased detail in design definition and weight calculations; 5. Material/equipment model changes during detail design and construction; 6. Deviation from construction drawings; 7. Shipyard unique design and construction techniques; 8. Increases in developmental systems? components. Because it is a fact that weight and KG increases will happen, it is important to account for them from the beginning of the design. This is done by adding margins to the weight estimate at the start of the design that are equal to the anticipated growth. Once these margins are established and there is a single design concept, the margins are then depleted to offset the growth in weight and KG as it occurs. This allows the design to remain at a constant displacement and KG that facilitates the overall design effort. For example, without margins any growth in KG could jeopardize stability and could require a major configuration change in a later design phase that is disruptive and costly. With margins, the stability can be validated early in the design and as long as the growth does not exceed the margins, the stability will remain satisfactory throughout the course of design and construction. Ideally, the ship will be delivered at the original estimated displacement and KG with no margins remaining. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/3015/buy}, author = {Redmond, Mark} } @conference {2466, title = {2466. Total Ship Weight Management Computer Program - For Today{\textquoteright}s and Tomorrow{\textquoteright}s Applications}, booktitle = {58th Annual Conference, San Jose, California, May 24-26}, year = {1999}, month = {5/24/99}, pages = {35}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {San Jose, California}, abstract = {Real-Time Ship Design Weight Estimate (RTSDWE99) is a comprehensive mass properties application that provides a sophisticated user interface along with the latest database technology to aid the mass properties engineer in preparing, monitoring, and predicting mass properties data as required by the Society of Allied Weight Engineers (SAWE) Recommended Practice No. 12, rev B. The software is based on established weight estimating methodologies built-into older software versions and expands those concepts along other newer ones by taking advantage of the capabilities and flexibility offered by the latest technologies in Graphical User Interfaces (GUIs), relational database functionality, and connectivity. With the addition of a new module for tracking engineering change proposals, and work-in-progress on the feasibility weight estimate module, RTSDWE99 has been transformed into an integrated system that can support mass properties operations from cradle-to-grave. RTSDWE99 calculates weights, moments, ship?s center-of-gravity, hydrostatics, moments-of-inertia, engineering changes, twenty station longitudinal weight distribution, and also facilitates external ad-hoc queries to the mass properties database The application was developed using MS Visual C++ and C, and is intended primarily for PC operation with Windows 95/98 or NT operating systems. The application has the capability to communicate with various Database Management Systems (DBMS) such as ACCESS, ORACLE, and INFORMIX by the use of Open Database Connectivity (ODBC) interface. The application software is comprised of dialog panels and child panels that help the user in preparing weight estimates. The dialog panels are tied to several database tables, and each panel has a fixed set of database functions. Functions are provided either by pull-down menus or standard and familiar database icons. These panels along with the standard database capabilities of search, add, modify, and delete, provide other advanced capabilities such as, modify-by- group, Query-by-Example, and others. The software has the capability to track several variants of a specific design within the same database. Also, an open dictionary capability is provided to track the engineering change proposals (ECPs) process, since this process is customized for each procurement program. ECPs are tracked from the proposal stage to the final adjudication and incorporation into the weight estimate. The program gathers mass properties information according to the requirements of the Society of Allied Weight Engineers (SAWE) Recommended Practice No. 12, rev B, through the use of interface panels by manual input, existing data - master files input, and properly structured output from computer aided design (CAD) systems. The software has extensive reporting capabilities. Output may be reported in several formats, such as customized text output, MS Word, MS Excel, and several other formats. The software provides for a full range of weight report options such as one, two, three digit and full or partial details, and various ECP reports.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/2466/buy}, author = {Ray, D and Filiopoulos, C} } @conference {2467, title = {2467. MAAST: A Distributed Agile Enterprise Approach to Ship Design}, booktitle = {58th Annual Conference, San Jose, California, May 24-26}, year = {1999}, month = {5/24/99}, pages = {29}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {San Jose, California}, abstract = {The U.S. shipbuilding industry needs a new way to compete in the global marketplace. Continued dependency on traditional ways of designing and building ships has resulted in forfeiture of a dominant position in commercial ship construction, which is an imperative for a great power. Surrendering to foreign competition will doom the U.S. maritime fleet to second- rate status in the next Century. One solution to this dilemma is creation of an enterprise to foster a collaborative engineering environment that could capitalize on the strengths of its members. In 1996, such an enterprise was formed in response to a government initiative. The enterprise employed a collaborative engineering environment and performed a pilot project as a proof of concept. This paper describes the process by which the enterprise developed the MAAST Program and performed the Pilot. The results of the Pilot are shown and lessons learned are provided to assist future enterprises.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/2467/buy}, author = {Tschabold, Gerald and Filling, J C} } @conference {2415, title = {2415. Generalized Mass Properties Formula Development for Submarine Analysis}, booktitle = {57th Annual Conference, Wichita, Kansas, May 18-20}, year = {1998}, month = {5/18/98}, pages = {49}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Wichita, Kansas}, abstract = {Throughout the normal process of analyzing mass properties data, it becomes apparent that the ordinary geometric shapes and their corresponding mass properties formulas normally published in textbooks and handbooks do not always adequately describe the component you are analyzing. This will present a problem if you are attempting, for instance, to determine the moments of inertia of a shell segment of a spheroid, cylinder, cone, etc. The geometric shapes that are analyzed in this paper are segments of some of the solids shown in the SAWE Weight Engineers Handbook under Section 4.2, Section Properties - Solids. The mathematical methods of determining the generalized formulas for volume, mass, moment as referenced from the axial planes through the object{\textquoteright}s origin, centroid, and moment of inertia as referenced about axes through the object{\textquoteright}s geometrical principle origin and centroid are described. The resulting derived formulas are somewhat long and complex. Therefore, to utilize them effectively and easily, they were incorporated into a spreadsheet format where only a few easily obtainable parameters are required for input. These formulas and samples of the spreadsheet format for each geometric shape are included as an appendix. This paper will also demonstrate that these sets of generalized formulas are able to effectively replace many of the formulas of solid shapes depicted in the Handbook, depending on the parameters which are chosen. This paper also recommends enhancements to the geometric shape codes and ""second-line"" input data used for item moment of inertia calculation, as described in the SAWE Recommended Practice Number 12.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/2415/buy}, author = {Voran, R W} } @conference {2416, title = {2416. Initial Applications of the Product Model in Developing Weight Estimates}, booktitle = {57th Annual Conference, Wichita, Kansas, May 18-20}, year = {1998}, month = {5/18/98}, pages = {31}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Wichita, Kansas}, abstract = {Traditional weight engineering skills and approaches, such as having in-depth knowledge of ship systems, historical data, and adequate manpower for drawing calculations may not be sufficient to produce quick and accurate weight estimates in today{\textquoteright}s acquisition reform-minded environment. As demand for technological and business innovation is increasing for upcoming designs, 3D-product modeling is expected to become a standard tool for design, manufacturing, and logistical support. Each CAD system offers certain inherent advantages and disadvantages. Therefore, weight engineers must make up for CAD system deficiencies or customize and expand CAD capabilities. They must have a working knowledge of relational databases and information extractions from design files to produce accurate results faster than the traditional labor-intensive approaches. However, since weight control is a time-based projection, starting from feasibility studies till the end of construction, traditional weight estimating methods must be maintained and integrated with product model data to project the mass properties of the ship, as required. The LPD 17 design has been the test case of the implementation of the Navy{\textquoteright}s CAD system for preliminary and contract designs. This paper describes our initial experiences in the mass properties area and the lessons learned.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/2416/buy}, author = {Filiopoulos, C and Marcavage, J and Ray, D and Tschabold, Gerald} } @conference {2417, title = {2417. SWATH Weight Engineering - A Case Study}, booktitle = {57th Annual Conference, Wichita, Kansas, May 18-20}, year = {1998}, month = {5/18/98}, pages = {17}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Wichita, Kansas}, abstract = {Small Waterplane Area Twin Hull (SWATH) ships present a unique challenge to naval architects and weight engineers. While SWATHs are surface ships, from a weight engineering standpoint they are different from conventional surface ships and actually have some features in common with submarines such as the necessity to operate at a constant displacement and the sensitivity to trim. This paper provides insight into the unique aspects of weight engineering on SWATH ships through an example case study. The T-AGOS 23 is the largest SWATH designed and constructed for the U.S. Navy and the experiences of this program will illustrate the unique aspects of a SWATH from the standpoint of weight engineering.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/2417/buy}, author = {Redmond, M} } @conference {2441, title = {2441. Shipweight: A Windows Program for Estimation of Ship Weights}, booktitle = {57th Annual Conference, Wichita, Kansas, May 18-20}, year = {1998}, month = {5/18/98}, pages = {24}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Wichita, Kansas}, abstract = {ShipWeight is a suite of computer programs for estimating and following up the weight and center of gravity of a vessel. When the programs are utilized in the course of systematically following up weight during the building phase, weights, centers of gravity, and other parameters are recorded and structured in such a way as to provide an optimal basis of empirical experience for estimating weights and centers of gravity in subsequent projects. In addition to presenting the methodology and computer technology utilized by ShipWeight, this paper also discusses a number of problems associated with vessel weight estimation and follow-up. The ""Introduction"" section of the paper goes through the background for the project, while the most central requirements and wishes that were specified before and during the project are discussed in the ""Weight System Requirements"" section. The systems and methodology that are behind ShipWeight are discussed in the ""ShipWeight Solutions"" section, while the computing solutions involved are described in the ""Experience in Use"" section. Since ShipWeight has only been in use for just over two years, our experience of using the system is still limited. Such experience as has been gained is discussed in the ""Experience in Use"" section.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/2441/buy}, author = {Aasen, R} } @conference {2356, title = {2356. Weight and KG Margin Analysis of Naval Surface Ships}, booktitle = {56th Annual Conference, Bellevue, Washington, May 19-21}, year = {1997}, month = {5/19/97}, pages = {40}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Bellevue, Washington}, abstract = {Effective weight and KG (height of vertical center of gravity above the keel acquisition margins are an essential element of the US Navy Weight Control Program. Acquisition margins are not only an engineering tool for making technical predictions, but impact the fiscal process as well. The need for continued improvement in margin determination was recognized when the weight control program was formulated in 1961. The first improvement came with the establishment of a formal margin policy in 1963. The values, restricted to weight at that time, reflected the best corporate engineering judgment based on scattered and, in many cases, unverified weight growths. Because the shipbuilding process is relatively long (compared to aircraft, land vehicle and missile production), it took fifteen years to accumulate a data base large enough to be considered reasonable for a statistical study of margins. In 1978 this data base was used to update the Weight Margin Policy for Surface Ships and expand it to include a KG margin policy, as well. In 1992, a study was undertaken to update the data base and find an appropriate statistical basis for margins prediction with an associated risk management approach to margin selection. This study verified the results of the 1978 study and supplemented the 1978 study by expanding and updating the Design \& Build (D\&B), Contract Modification (Con Mod), and Government Furnished Material (GFM) data sets. This paper discusses the statistical results of the data, and includes recommendations for updating the current NAVSEA Weight and KG Margin Policy. In addition, a formal margin selection method is presented which produces margins for each design phase and an associated quantifiable risk of exceeding them. Using this method, a Ship Design Manager working with the weight engineer (mass properties) can select a level of risk appropriate for his (her) design and determine weight and KG margin values associated with this risk.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/2356/buy}, author = {Dominick Cimino and Filiopoulos, C} } @conference {2301, title = {2301. Docking Support for Lift Transfer of USS Osprey (MHC-51)}, booktitle = {55th Annual Conference, Atlanta, Georgia, June 3-5}, year = {1996}, month = {6/3/96}, pages = {10}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Atlanta, Georgia}, abstract = {History was made during the summer of 1995. For the first time, a commissioned Naval Ship was moved on a barge and across land into an inland body of water. Several military activities worked together to accomplish this feat. Factors for selecting Norfolk Naval Shipyard as the docking facility included dry dock depth and availability of a dry dock in relation to the Lift Transfer time table. This paper discusses the role that Norfolk Naval Shipyard (NNSY) performed in this evolution. NNSY dry-docked the USS OSPREY (MHC-51) on a barge in preparation for towing to Maryland. The ship was then transported using a rail system to its fresh water destination for testing. Upon completion of testing, the USS OSPREY returned to the barge for its journey back to NNSY. After undocking from the barge, the USS OSPREY left the Chesapeake Bay and returned to the Atlantic Ocean. Completion of the lift transfer required ten (10) docking/undocking evolutions; Six (6) of these evolutions took place at NNSY. At NNSY the barge was dry-docked and flooded to sit on the bottom of the dry dock. The ship floated in over the barge and landed in a cradle on the barge. The docking crew utilized extreme precision and patience to accurately place the USS OSPREY (MHC-51) on the cradle. The process was reversed when the ship was returned to the Atlantic Ocean. In addition to standard docking/undocking calculations, constant pumping calculations and monitoring of the tank levels was required to support flooding/dewatering of the dry dock and barge. The entire Lift-Transfer Evolution was completed on time and under budget. The success of the lift transfer was possible due to the cooperative work of several government facilities along with the support of private corporations.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/2301/buy}, author = {Lester, A} } @conference {2013, title = {2013. Naval Ships Weight Moment of Inertia}, booktitle = {50th Annual Conference, San Diego, California, May 20-22}, year = {1991}, month = {5/20/91}, pages = {24}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {San Diego, California}, abstract = {This paper discusses the results of an overall effort to enhance mass properties capabilities by the development of a computer tool to calculate weight moment of inertia/gyradius values for naval ships. This capability was incorporated into the Navy{\textquoteright}s ship design weight estimating family of computer programs (SDWE/UPDAT). This paper provides the documentation necessary to produce weight moment of inertia/gyradius data and provides guidance in estimating as well as calculating inertia values.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/2013/buy}, author = {Dominick Cimino and Redmond, M} } @conference {1920, title = {1920. Modification of the SDWE System to Calculate Gyradius}, booktitle = {49th Annual Conference, Chandler, Arizona, May 14-16}, year = {1990}, month = {5/14/90}, pages = {26}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Chandler, Arizona}, abstract = {The ability to predict ship motions has become increasingly important over the last several years. This is especially true when considering the number of recent ship designs with unconventional hull forms (i.e., Small WAterplane Twin Hull (SWATH), Surface Effect Ship (SES), etc.). Consequently, the necessity to predict ship motions by calculating the gyradius of the ship in the early stages of a ship design has become essential. The once valid method of using ""rules of thumb"" based on historical data has come into question and is considered unreliable for unconventional hull forms. Instead, the ability to calculate gyradius using the weight estimate is considered an effective and efficient way to accomplish this. Therefore, a Plan of Action and Milestones (POA\&M) to develop the design tool to calculate gyradius was initiated. The focus of this effort was to modify the Ship Design Weight Estimating (SDWE) family of programs. The modifications to the computer programs result in the ability to calculate weight moments of inertia for roll, pitch, and yaw (in air) and ultimately in the calculation of the gyradius of the ship in air.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1920/buy}, author = {Dominick Cimino and Huang, K N and Redmond, M and Vasquez, D} } @conference {1805, title = {1805. Austerity Vs Enhancement - The Challenge of the AO-177 Jumbo Contract Design}, booktitle = {47th Annual Conference, Plymouth, Michigan, May 23-25}, year = {1988}, month = {5/23/88}, pages = {33}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Plymouth, Michigan}, abstract = {This paper describes the contract design weight estimate process for jumboizing the AO 177 Class Fleet Oiler. It began with a statement of the Navy{\textquoteright}s design goals and culminated in the issuance of three complete weight estimates reflecting three different versions of a jumboized oiler: the enhanced oil-only, the austere oil-only, and the oil-munitions version. The success of the weight estimate effort is largely due to organization of the weight data base and careful attention to detail while ensuring the continuity, integrity, and timeliness of the weight estimating process. This allowed a flexible response to changing requirements and early forecast of weight and moment trends.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1805/buy}, author = {Tschabold, Gerald} } @conference {1806, title = {1806. Controlling Mill Tolerance on T-Agos 19, Interim Report}, booktitle = {47th Annual Conference, Plymouth, Michigan, May 23-25}, year = {1988}, month = {5/23/88}, pages = {14}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Plymouth, Michigan}, abstract = {Steel plate constitutes about 50\% of the lightship weight on the T-AGOS 19. Mill tolerance would normally add 5\% to the actual weight of the plates as rolled. Through the utilization of Controlled Gage Plate on this project, McDermott Marine Construction is experiencing an actual mill tolerance of 0.7\%, with 40\% of the ship{\textquoteright}s plates weighed as of march 16, 1988. If this trend continues, a net saving in excess of 1.5\% of lightship is projected. This paper outlines standard plate tolerances and McDermott{\textquoteright}s experience with actual weights using Controlled Gage Plate. Charts and graphs summarizing actual weights and tolerances are included. Controlled Guage Plate is defined. Comparisons with Precise Weight Plate are made. Recommendations regarding the use of these mill services are offered.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1806/buy}, author = {McMahon, J and Meche, K J} } @conference {1708, title = {1708. Mass Properties Reporting}, booktitle = {45th Annual Conference, Williamsburg, Virginia, May 12-14}, year = {1986}, month = {5/12/86}, pages = {8}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Williamsburg, Virginia}, abstract = {The Equilibrium Maintenance Program was developed for the purpose of tracking the weight and stability conditions of each submarine in a class of ships during its service life. It can be used for any class of submarine for the US Navy. In order for the program to provide reliable information, the personnel in charge must devote full time to its update and constantly pursue the needed data from each activity involved with the ships. Two major benefits resulting from this program are: 1.) Accurate growth margin for future changes 2.) Advance reballasting information before overhaul.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1708/buy}, author = {Bridges, G B} } @conference {1713, title = {1713. A Weld-Stud/Stud-Pad Method for Foundationing Lightweight Shipboard Equipment}, booktitle = {45th Annual Conference, Williamsburg, Virginia, May 12-14}, year = {1986}, month = {5/12/86}, pages = {30}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Williamsburg, Virginia}, abstract = {The introduction of new and advanced equipment, and the growth of supporting systems such as cooling water and ventilation aboard ship, provide today{\textquoteright}s weight engineer with a constant challenge to develop means to control and reduce ship displacement. The sheer volume of equipment installed on a modern ship dictates that efficient, cost effective means be employed when foundationing this equipment. Standardization of foundations for similar items is not only desirable, but is necessary in order to maintain efficiency and control weight. Standardization of foundations, however, can lead to a situation where the support system is designed to suit a range of equipment sizes and weights. This results in foundations which are adequate at the high end of equipment weight, but overdesigned and excessively heavy at the low end of equipment weight. This paper describes the development of a lightweight foundationing system, developed by Ingalls Shipbuilding, Division of Litton in Pascagoula, which utilizes weld-studs and stud-pads in a wide range of applications for equipment weighing up to l00 pounds. Although weld-studs and stud-pads have been used in the shipbuilding industry for many years, the problem which has existed has been the lack of data providing direction on the load carrying capacity of these systems. Varying conditions caused by equipment stand-off from the mounting surface, equipment weight, center-of-gravity location, fastener size and type of material, have raised many questions as to the adequacy of stud-type foundations aboard ship. 1ack of data has resulted in the ripout of some installations because insufficient information was available to prove the adequacy of the stud/pad foundation. The system developed by Ingalls provides the user with a pre-engineered set of tables which contain load-carrying capacities for a wide variety of equipment in a broad range of mounting conditions.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1713/buy}, author = {Beausoleil, L J} } @conference {1650, title = {1650. CAD/CAM Mass Properties}, booktitle = {44th Annual Conference, Arlington, Texas, May 20-22}, year = {1985}, month = {5/20/85}, pages = {20}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Arlington, Texas}, abstract = {In the shipbuilding industry, it is relatively common knowledge that CAD/CAM (Computer Aided Design/Computer Aided Manufacturing) systems can generate accurate and consistent drawings. These drawings can then be utilized for production support lofting, parts generation, reference material and so forth. However, one of the most significant advantages of utilizing a CAD/CAM system is not so commonly known: the development of a design database. While conventional computer systems generate, store and analyze numerical and/or textual databases, CAD/CAM systems generate, store and analyze databases of graphics. This paper illustrates methods which optimize use of a graphic database, focusing on the application of CAD/CAM analytical capabilities to mass properties analyses (as practiced in naval ship design). These methods are results of combining CAD/CAM technology with existing systems and knowledge to achieve cost effective technically superior, more accurate methods of performing engineering tasks. Accordingly, methodology, actual productivity comparisons and other related applications will be presented. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1650/buy}, author = {McNeal, J C} } @conference {1652, title = {1652. The Expanded Ship Work Breakdown Structure (ESWBS) - Another Weight Classification System}, booktitle = {44th Annual Conference, Arlington, Texas, May 20-22}, year = {1985}, month = {5/20/85}, pages = {42}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Arlington, Texas}, abstract = {This paper examines the application of the Expanded Ship Work Breakdown Structure (ESWBS) level of detail to the task of weight estimating and accounting. The Expanded Ship Work Breakdown Structure Manual expands the currently used Ship Work Breakdown Structure (SWBS) Manual through the addition of two digits to fit maintenance world requirements. The ESWBS is based on the original SWBS concept and the first three digits of ESWBS are identical to SWBS. The advantages for developing the ESWBS manual are a better defined functional configuration definition of the ship for logistic support development and a common reference point for 1inking 1ogistic support data to design. The ESWBS manual will now be used for configuration identification and change reporting throughout the ship life cycle. The use of ESWBS establishes the common reference point and interface mechanisms between design, the shipbuilder{\textquoteright}s contract baseline, the maintenance and logistic support baselines and the ship{\textquoteright}s configuration baseline resident on the Weapons Systems File (WSF). ESWBS is now the minimum standard level of indenture for developing, identifying, and reporting configuration changes generated by Ship Alterations performed on non-structured or structured ships. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1652/buy}, author = {Kelley, J R} } @conference {1653, title = {1653. Marine Applications of Composite Materials}, booktitle = {44th Annual Conference, Arlington, Texas, May 20-22}, year = {1985}, month = {5/20/85}, pages = {56}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Arlington, Texas}, abstract = {Composite materials have been gaining increasing popularity in all fields of engineering design. Although the marine field has been slower in accepting these materials, their use is now becoming more prevalent in this field. The small boat field has seen the greatest use of these materials and now larger vessels are following suit. The purpose of this paper is to provide general information about specific materials which have applications in the marine field to naval architects and marine engineers who have had little exposure to these relatively new materials. The properties of the various constituents are described as well as discussions of the various fabrication techniques which can be used. This discussion is limited to those materials used in the marine industry, which are glass, KEVLAR and other aramids, and graphite. An emphasis is placed on the weight savings characteristics of these materials, since the primary reason for their use is to save weight. The specific applications of these composite materials in the small boat applications are discussed. Current trends in hull design and construction are discussed as well as other developments in the construction of spars and bulkheads. The discussion of the applications for larger vessels is far ranging, from current proven applications to potential hypothetical applications. These potential applications are discussed only from the standpoint of first principles. There has been little or no hard engineering done in any of these areas. It is intended for these discussions to highlight potential applications which should be examined and developed further. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1653/buy}, author = {Redmond, M A and McKesson, C B} } @conference {1655, title = {1655. Training of Mass Properties Engineers}, booktitle = {44th Annual Conference, Arlington, Texas, May 20-22}, year = {1985}, month = {5/20/85}, pages = {21}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Arlington, Texas}, abstract = {The need for Mass Properties Engineers is growing in the Marine Industry. In order to meet this demand at Ingalls Shipbuilding, a comprehensive training program was initiated. The objective of this paper is to outline a program to train people to carry out the assigned function of a Mass Properties Engineer. Listed below are qualifications you would expect a trainee to have after completing the training course and working a year in the Mass Properties Engineering field. 1. Be able to read blue prints and have knowledge of drawing/design development and production techniques. 2. Be able to utilize empirical and analytical equations, structural analysis techniques, and electronic computing equipment. 3. Possess extensive knowledge of materials and how they can be employed to the best weight advantage. 4. Have a working knowledge of electronic, mechanical, electrical, hydraulic, heating, ventilation, air conditioning, armament and propulsion systems. 5. Possess a thorough knowledge of principles of Naval Architecture, especially in hydrostatics, geometry of ship and stability (inclining experiment) area. 6. Be well versed in weight reporting techniques, identifying adverse trends and making recommendations to correct weight and KG problems. In order to carry out the above functions, individuals must be selected that usually have a degree in Aeronautical, Civil, Mechanical or Electrical Engineering or a degree in Naval Architecture. A degree in Math, Computer Science and Industrial Arts is also acceptable along with non-degreed people with extensive shipyard experience. Degreed or experienced individuals (at least one year in Engineering within the shipyard) selected, can be trained in 36 classroom hours to become productive Mass Properties Engineers in a lead position. This paper is intended to give marine, and with some correlation, aeronautical industries, an approach to training their employees in the mass properties field. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1655/buy}, author = {Shamburger, C J} } @conference {1601, title = {1601. Mass Properties Control - Program Inspections, Necessary and Useful}, booktitle = {43rd Annual Conference, Atlanta, Georgia, May 21-23}, year = {1984}, month = {5/21/84}, pages = {13}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Atlanta, Georgia}, abstract = {When a ship is in the design phase, the dimensions, power, strength and arrangements are influenced by estimates of the mass properties of all items to be included in the ship. Experience has shown that despite extreme care in this initial estimating, the mass properties of the ship do increase during the design development and building periods. If a ship is allowed to grow beyond the limits set forth in the basic design, it will not only restrict its operational capabilities but may reduce service life capabilities through costly ballasting, rearrangement or shifting of loads or other severe corrective action. In any ship design, a mass properties control program must be applied beginning with the first feasibility studies and continuing through preliminary design, contract design, detail design and construction. During detail design and construction, the mass properties control program includes a group of functions broadly classified as monitoring and. control. Monitoring includes functions that verify the mass properties estimates and control functions are those which cause the compilation of "before-the-fact" reports, detect trends, and evaluate corrective measures in a timely manner. Mass properties control, then, requires a continuous inspection system to be implemented and maintained to ensure compliance with program requirements throughout detail design and construction.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1601/buy}, author = {Kelley, J R} } @conference {1602, title = {1602. Ship Weight Estimates Using Computerized Ratiocination}, booktitle = {43rd Annual Conference, Atlanta, Georgia, May 21-23}, year = {1984}, month = {5/21/84}, pages = {73}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Atlanta, Georgia}, abstract = {Although the method of ratiocination is well known for use in preparing ship weight estimates during the early design phases, this method when done using hand calculations is cumbersome and does not lend itself well to the rapidly changing and fluid designs characteristic of the early stages of naval ship design. This need to provide a more convenient and rapid method for producing a weight estimate based on minimal ship information, without any loss of accuracy, led to the use of computers and the development of the RATS program to produce these estimates. The RATS program is an interactive program developed to use a pre-selected known base ship and certain selected characteristics of the new ship design to produce a complete three-digit SWBS weight estimate containing the weights and vertical and longitudinal centers for the design. This is done by the program through a series of equations which equate the SWBS element weight and centers with certain characteristics of the new ship, which then modify the base ship weight to reflect the new design characteristics. Since this methodology is subject to some inaccuracies if the new design has a somewhat different configuration or mission than the base ship, the program also allows the user to modify the estimate produced by this method to reflect any of the special or unique aspects of the new design. The output of the program is an eleven page estimate which also contains the base and new ship characteristics. Also produced is a summary of all of the modifications made to the estimate by the user. Options also exist to produce a delta summary from the base ship to the new ship, to prepare the estimate in a format compatible for input into the SDWE program, and to use the new ship estimate as a base ship file for sensitivity studies. The estimate may be prepared using either English or metric units. This program has several applications. Most importantly, it allows the engineer to prepare an accurate weight estimate for a naval ship during the Feasiblity level of design in a very short amount of time. It also allows sensitivity analyses to be performed on a ship at virtually any level of design, again in a very short period of time. These sensitivity analyses would determine the impact of variation in the ship characteristics to the ship weight and centers of gravity. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1602/buy}, author = {Redmond, M A} } @conference {1603, title = {1603. Submarines - Stability and Equilibrium}, booktitle = {43rd Annual Conference, Atlanta, Georgia, May 21-23}, year = {1984}, month = {5/21/84}, pages = {13}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Atlanta, Georgia}, abstract = {Although submarines have been in use for years, many operators and those not intimately involved with stability and equilibrium do not appreciate and fully understand the need for weight control measures necessary to ensure that stability and equilibrium are maintained. Based on many years of experience, it has been learned that many commanding officers of submarines do not want lead ballast adjustments made after successful sea trials in which no difficulties were encountered with diving and controlling their vessel. However, this successful dive is based on only one particular load condition. For the submarine to be effective it must be able to successfully operate in numerous conditions of loading. This often necessitates the adjustment of lead ballast based on the successful dive that the submarine{\textquoteright}s operators have witnessed. Part of this lack of understanding and hesitancy to concur with re-ballasting requirements is because the operators are not aware of the various evolutions that the ship yards are required to perform to ensure that the ship is properly ballasted for sea trials and then for delivery. In order to provide a basis for dealing with the situation described above, a brief discussion of the evolutions the ship yards are required to perform, along with definitions and examples, is necessary. The topics to be discussed are stability, inclining experiment, submerged displacement, diving trim, equilibrium polygon, load to submerge, trim dive, and weight and moment. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1603/buy}, author = {Dudley, J R} } @conference {1606, title = {1606. Review of Ship Specifications for Weight Latitudes}, booktitle = {43rd Annual Conference, Atlanta, Georgia, May 21-23}, year = {1984}, month = {5/21/84}, pages = {34}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Atlanta, Georgia}, abstract = {In recent years, ships{\textquoteright} weight estimates have experienced significant weight growths as evidence by the difference between Contract Design Weight Estimates and Final Weight reports. In an attempt to reduce those differences, an investigation was undertaken to identify major contributing factors. One of those factors, associated with development of ship specifications to performance oriented requirements, was identified to be the latitudes provided shipbuilders in the ship{\textquoteright}s specifications. Performance oriented specifications tend to permit latitudes which usually result in weight variances. This paper addresses and attempts to quantify the weight and associate KG impacts of those specification latitudes. Thirty-two SWBS elements, where significant weight growths have occurred and where performance oriented specifications exist, were selected for review. Three ship designs reflecting present design philosophy latitude weight/KG variance of 1.73\% to 2.64\% of lightship weight, and an associated 1.41\% to 2.09\% of full load KG exists. In order to significantly increase the chances of precluding the occurrence of these specification latitude weight variances on future designs any one or a combination of the following three actions can be taken: revise specifications to eliminate or reduce latitudes; incorporate latitude weight variances in estimates for affected three-digit SWBS elements; and or revise weight and KG margin values to account for latitude weight variances. In summary, this paper documents the weight variances due to the latitudes in the ship specification for the 32 SWBS elements investigated. The results contain several significant findings and recommendations. The prime objective of this study was to identify areas where revisions to the ship specifications can be made in order to be more specific and reduce the latitudes provided to the shipbuilders. If revisions the specifications can no be made in initial weight estimates. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1606/buy}, author = {Dominick Cimino} } @conference {1607, title = {1607. A Case for the Elimination of Weight and Kg Margins From Ship Weight Estimates and Reports}, booktitle = {43rd Annual Conference, Atlanta, Georgia, May 21-23}, year = {1984}, month = {5/21/84}, pages = {7}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Atlanta, Georgia}, abstract = {Historically, weight and KG (height if vertical center of gravity above the keel) margins have been an essential element of any ship weight control program. Margins are not only considered an engineering tool for making technical predictions, but are generally embodied in the fiscal process as well. In many instances, the non-engineering acquisition community has often identified margin reduction as a legitimate weight eliminating margins from the weight estimate. The end result should improve the overall accuracy of the weight estimates.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1607/buy}, author = {Kern, P H and Kelley, J R} } @conference {1532, title = {1532. U.S. Navy Surface Ship Weight and Kg Margins Revisited}, booktitle = {42nd Annual Conference, Anaheim, California, May 23-25}, year = {1983}, month = {5/23/83}, pages = {15}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Anaheim, California}, abstract = {Effective weight and KG (height of vertical center of gravity above the keel) margins are an essential element of the U.S. Navy Weight Control Program. Margins are not only an engineering tool for making technical predictions, but are embodied in the fiscal process as well. The need for improvements in margin determination was recognized, when the weight control program was formulated in 1961. The first improvement came with the establishment of a formal margin policy in 1963. The values, restricted only to weight at that time, reflected the best corporate engineering judgment based on scattered and,in many cases, unverified weight growths. Because the shipbuilding process is relatively long (compared to aircraft, land vehicle and missile production), it took fifteen years to accumulate a database considered reasonable for a statistical study of margins. These data were used to update the NAVSEA weight margin and to establish a KG margin policy in 1978. The data used in this paper supplements the 1978 data and statistical studies are presented based on all data, previous data only, and new data only. This paper discusses the results of the various studies and includes conclusions and recommendations concerning updating of the NAVSEA Weight and KG margin policy. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1532/buy}, author = {Kern, P H and Kelley, J R} } @conference {1533, title = {1533. Fundamentals of Naval Surface Ship Weight Estimating}, booktitle = {42nd Annual Conference, Anaheim, California, May 23-25}, year = {1983}, month = {5/23/83}, pages = {44}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Anaheim, California}, abstract = { This paper describes how ship weights are estimated. Detail is presented concerning relationships between existing weight data and the characteristics of a new design as it developed from completion of feasibility design through contract design. Margin requirements are also discussed. The weight estimating ratios and factors presented, while not directly associated with a specific ship type, cover the weight classification groups one would use in the design of a surface combatant. The purpose of this paper is to present the fundamentals of weight estimating to the ship design community. With this knowledge, ship design engineers and managers should be able to personally identify with the important parts they all play in creation of a credible (or incredible) weight estimate. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1533/buy}, author = {Straubinger, E K and Curran, W C and Fighera, V L} } @conference {1534, title = {1534. Cut and Splice a Method of Weight Estimating for Naval Ship Design}, booktitle = {42nd Annual Conference, Anaheim, California, May 23-25}, year = {1983}, month = {5/23/83}, pages = {27}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Anaheim, California}, abstract = {During Preliminary Design Session of the 1983 SAWE International Conference, the Algorithm Mass- Factoring Method (AM-FM)*, for determination of realistic weights from the theoretical weights of any finite element model (FEM) structural optimization and analyses program (SOAP), was presented. The algorithmic method is based on the premise that for any structure, when reduced to elementary components as in a finite element model, the elements can be described in terms of simple functions. These functions are easily determined. For example - a plate (cover, web, membrane) element; is capable of carrying and transferring certain tupes of loads; may be stiffened in some manner to yield a valid realistic weight for that element. In a similar manner, the weight of beam elements can be determined. It was noted, based on the above premise, that the AM-FM is applicable to any type of structure (aircraft, missile, space vehicle, automobile, buildings, etc.) that may be analyzed by FEM-SOAP{\textquoteright}s. One of the major areas of concern was the unknown effect of FEM grid-density on both the SOAP sizing and the AM-FM weights. The purpose of this paper is to present the results of an analyses of a wing box using three levels of element grid-density. Further, a modeling technique variation was included. The variable technique studied was the modeling of plate stiffeners as beam or rod elements versus the effect of being modelled as lumped stiffeners. The study shows that the AM-FM method of finite element model weight determination is self-adapting and insensitive to grid-density variations.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1534/buy}, author = {Burch, G J} } @conference {1535, title = {1535. Installation of Lead Ballast on Naval Submarines}, booktitle = {42nd Annual Conference, Anaheim, California, May 23-25}, year = {1983}, month = {5/23/83}, pages = {9}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Anaheim, California}, abstract = {With the continuing increase in cost and size of naval submarines, any area where construction can be accomplished more efficiently should be explored. As prosaic an item as lead ballast installation is an area where improvements can be made. For the most part, ballast installation has not changed since the fleet type boats of World War II. It is essentially a haphazard procedure; particularly with the first ship of a class. This paper will discuss some techniques for improving lead ballast installation in naval submarines. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1535/buy}, author = {Brustolon, E A} } @conference {1536, title = {1536. Weight Control, the Challenges Associated With a New Outlook on an Old Problem}, booktitle = {42nd Annual Conference, Anaheim, California, May 23-25}, year = {1983}, month = {5/23/83}, pages = {36}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Anaheim, California}, abstract = {This paper represents the combined and centroids effort of a dedicated group of people committed to the control of weight on ships. This paper covers the organization, and whatit is to accomplish. The goals are accomplished through a procedure of allocation and control initiated at contract design and tracked and monitored through the entire engineering and construction process. It amplifies a concept of weight reduction initiated early in the design process both by education and change. Such things as methods used, material changes are discussed. Monitoring and control of equipment weights both contractor and government furnished are discussed. Some of the studies that were involved in providing more accurate data are discussed in some detail. These include such things as the scale weighing program, the study on mill tolerances on plates and the actions taken. Personnel acquisitions and the challenges involved in obtaining and indoctrinating the individuals are addressed. Education of the weight control process is an ever continuing task. The organizational interfaces required both within and external are reviewed. This paper uses specific examples of various studies and areas of interest to show the challenges encountered in the Weight Control evolution. The goal is to control weight yet being flexible enough to allow evolution of design, thereby providing ships that will be compatible with the state-of-the-art systems that are being installed in them. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1536/buy}, author = {Bonney, J W} } @conference {1537, title = {1537. Destroyer Synthesis Computer Algorithm (DESCA)}, booktitle = {42nd Annual Conference, Anaheim, California, May 23-25}, year = {1983}, month = {5/23/83}, pages = {34}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Anaheim, California}, abstract = {The Destroyer Synthesis Computer Algorithm (DESCA) program was developed to reduce the convergence time in the feasibility/concept design process for destroyer-type ships. The program is designed to satisfy given stability requirements, i.e., beam to GM ratio. The program is an interactive type of model that queries the user in order to establish ship parameters. The program calculates various ship parameters such as ship size (length, beam, depth and draft), ship{\textquoteright}s internal volumes, weights, and centers of gravity. This program has proven to be an effective tool in establishing a baseline weight estimate. It has saved considerable time in establishing starting points for feasibility studies. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1537/buy}, author = {Robbins, J F} } @conference {1463, title = {1463. Description of the Interactive Submarine Ballast Program}, booktitle = {41st Annual Conference, San Jose, California, May 17-19}, year = {1982}, month = {5/17/82}, pages = {18}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {San Jose, California}, abstract = {This paper is intended to document and provide a user{\textquoteright}s guide for the Interactive Submarine Ballast Program developed initially by NAVSEA code 32122. The Interactive Submarine Ballast Program allows an engineer to execute a computation cycle to determine the stability and trim ballast requirement of a submarine. At the beginning of each cycle of calculation the engineer has the option of modifying the input parameters. The scope of this paper will cover the software and hardware requirements of the program and a basic discussion of the algorithms used in the calculation cycle. Included in appendices are listings of an input file and a typical output resulting from the input file. The source listing of the program is available to any user requesting it through the Naval Sea Systems Command code 32122 located in Arlington, Va. Due to the length of the listing, it was not included in the paper.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1463/buy}, author = {Batchelor, B L} } @conference {1307, title = {1307. Weight Control of US Naval Ships at Norfolk Naval Shipyard}, booktitle = {38th Annual Conference, New York, New York, May 7-9}, year = {1979}, month = {5/7/79}, pages = {53}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {New York, New York}, abstract = {Weight control, not merely weight reporting, must be observed on U.S. Naval Ships throughout their service life. It must be remembered that U.S. Naval Ships must have the ability to perform the mission intended under adverse conditions. Combatant ships are platforms for launching weapons and aircraft. These ships must have adequate stability and reserve buoyancy so that they can success fully launch their weapons and aircraft even under damaged conditions. If an inherent list or trim condition exists, and the ship is unable to correct it, the launching of weapons and aircraft can be greatly impaired. Many amphibious ships must have the ability to beach: their displacement, list, and trim condition must be maintained to insure the completion of their mission. Auxiliary ships which provide support for the fighting navy also have stability problems, such as excessive weight, high vertical center of gravity, list, and trim problems which must be continually monitored. Providing good working conditions and personal comfort aboard naval ships are important considerations. A ship with a short and rapid period of roll could cause injury to its personnel or hinder ship{\textquoteright}s force from performing its duties. By monitoring and controlling stability, ship{\textquoteright}s force can more easily perform their intended mission. Naval shipyards{\textquoteright} weight control responsibility to naval ships is to insure prove the capabilities of a ship. The possibility of helping naval ships ranges widely and some of the actions will be discussed in the paper. Weight and moment reporting also develops historical data which can be used to monitor changes in weight and moment that occur over a period of years. This data may be used to improve ship design so that needed margins may be planned for future ships and equipment not used by existing ships maybe eliminated in future designs. This paper will explain how the Norfolk Naval Shipyard implements the Navy{\textquoteright}s Weight Control Program in the ship repair and modernization program. It will also explain how our shipyard strives to accomplish more than simply reporting weight and moment changes by trying to improve the stability characteristics of the ships overhauled by this shipyard. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1307/buy}, author = {Counts, J G} } @conference {1237, title = {1237. A Statistical Approach to Naval Ship Weight Estimating}, booktitle = {37th Annual Conference, Munich, West Germany, May 8-10}, year = {1978}, month = {5/9/78}, pages = {18}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Munich, West Germany}, abstract = {Effective weight prediction methods are an essential element of the U. S. Navy Weight Control Program. Ratiocination method is currently used to estimate three digit element weight data for preliminary and contract design level weight estimates. This method is considered inadequate when no parent or similar ship is available. This paper presents an approach that utilizes standard empirical curve fitting routines to develop equations including associated standard deviation values. These equations and standard deviation values are used to arrive at one digit group level weight with a corresponding standard deviation. This method is not new but its application to marine weight estimating has been very limited.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1237/buy}, author = {Kern, P H} } @conference {1238, title = {1238. Royal Navy Surface Ship Weight Design}, booktitle = {37th Annual Conference, Munich, West Germany, May 8-10}, year = {1978}, month = {5/9/78}, pages = {14}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Munich, West Germany}, abstract = {This paper discusses the methods in use in Ship Department, Ministry of Defense, for the estimation, recording and control of weight of surface warships. It first explains the need for the control of weight, and then discusses the methods used in the various stages of a design. In particular the application of these methods to the computer as part of a comprehensive ship design suite of programs is described. Some problems associated with shipbuilding weight recording and control systems are discussed. The analysis of the completed ship weight returns is discussed as well as the checks kept on running ships. Finally, the present organization for weight design in Ship Department is described.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1238/buy}, author = {Orton, P C} } @conference {1187, title = {1187. Inclining Experiment Uncertainty Analysis}, booktitle = {36th Annual Conference, San Diego, California, May 9-12}, year = {1977}, month = {5/9/77}, pages = {22}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {San Diego, California}, abstract = {A ship{\textquoteright}s safety and ability to meet performance requirements are highly dependent on its stability characteristics. In that a ship{\textquoteright}s stability characteristics have a direct relationship to the vertical center of gravity, it is essential that proper consideration be given to possible inaccuracies in the vertical center of gravity when evaluating a ship{\textquoteright}s stability characteristics. The accepted method of validating the mass properties characteristics of a ship is the inclining experiment. The purpose of this paper is to delineate procedures and analyses that can be used to establish the magnitude of the uncertainties in the vertical center of gravity of the ship as determined by the inclining experiment.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1187/buy}, author = {Wood, N L} } @conference {1188, title = {1188. Weight, Stability, and Subdivision Considerations in the LHA-1 Class Design}, booktitle = {36th Annual Conference, San Diego, California, May 9-12}, year = {1977}, month = {5/9/77}, pages = {13}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {San Diego, California}, abstract = {This paper presents the weight, stability, and subdivision considerations that were instrumental in the development of the General Purpose Amphibious Assault Ship, LHA-1 Class, design configuration. Criteria for stability and reserve buoyancy conflicted with the unique cargo arrangement requirements. The definition of the water tight envelope resulted from various analyses which arrived at a design solution providing an acceptable ship with minimum impact on cargo stowage and handling. The paper describes how the criteria were satisfied and the analyses that were conducted to define the key dimensional constraints. The success of the ship concept itself was dependent upon valid initial estimates of displacement and center of gravity. Early adverse trends in the transverse center of gravity required major design changes; fortunately, these changes were accomplished in the concept design phase. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1188/buy}, author = {Johnson, H B} } @conference {1190, title = {1190. An Interpretation of the Navy Weight Control Program}, booktitle = {36th Annual Conference, San Diego, California, May 9-12}, year = {1977}, month = {5/9/77}, pages = {16}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {San Diego, California}, abstract = {The immediate objective of this paper is present to the Engineer who is about to enter the field of Navy Weight Control, a summary of the Weight Control Program with emphasis on those areas wich one can expect to encounter in detail design state of Weight Control. The basic assumption is that it is imperative that we impress on the engineer, new to our work, the importance of the Navy Weight Control Program to the overall ship design and thus to hopefully install a pride in this task and the incentive to be a useful member of the Weight Control Team. In this treatise every effort will be made to accurately and informatively present pertinent facts and guidelines with regard to Weight Control as currently practiced. The intention is not, however, to provide the experienced Weight Control Engineer with a new text covering the policies of weight control, weight estimating and weight reporting. The paper explains the purpose of weight control relative to naval vessel design with emphasis on the importance of timeliness, detectors of undesirable trends and devising of corrective measures. It stresses the importance of effective liaison between the design engineer and the weight engineer. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1190/buy}, author = {Wanker, C R} } @conference {1191, title = {1191. Marine Disasters Related to Mass Properties or Stability}, booktitle = {36th Annual Conference, San Diego, California, May 9-12}, year = {1977}, month = {5/9/77}, pages = {9}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {San Diego, California}, abstract = {Operation of marine vehicles is a hazardous at best, and the difficulty is severely compounded when attention is not given to elementary (or even intuitive) mass property or stability principals. The history of disasters at sea is as old as the history of man on or in the sea, but great loss through a lack of understanding of basic concepts remains a preventable tragedy. This paper will re-emphasize by example why our profession must never become complacent. There are many of us who have not fully made the connection between our software work and the physical world of ships at sea. Each mass properties engineer in shipbuilding must realize he is certainly as responsible for the successful performance of the ship as anyone else on the project. This paper will attempt to establish the connection. Several cases have been selected of marine casualties (both great and small) which illustrate how some of these fundamental precepts were violated and subsequent results. Examples of the cases are the GREAT EASTERN (improper weight calculations before launch), USS ALAMAGORDO (shifting weights), SS NORMANDIE (adding topside weights and free surface), SS MANCHURIA (adding trimming weights), and USS SPRUANCE (weight and buoyancy curves mismatch). We can learn from our mistakes or we can repeat them. As Bruke said in 1792, {\textquotedblleft}Early and provident fear is the mother of safety.{\textquotedblright} If we do not fear these types of disasters because we are far removed from them in distance, time, or job application, let us at least respect them through understanding their cause and prevention.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1191/buy}, author = {Hallock, J F} } @conference {1192, title = {1192. Methodology to Qualify and Quantify Preliminary Ship Design Weight Estimates}, booktitle = {36th Annual Conference, San Diego, California, May 9-12}, year = {1977}, month = {5/9/77}, pages = {66}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {San Diego, California}, abstract = {A methodology and approach to qualify and quantify a preliminary ship design weight estimate are presented. Consideration is given to the requirements of the ship Owner/operator and those priorities which must be addressed at the initial outset of the preliminary weight estimate. Various methods and approaches to estimating Steel, Outfitting and Machinery are addressed and the extent to which individual MARAD sub-group weights should be estimated. Conclusions are drawing with regards to these elements o the preliminary weight estimate which should retain priority and those which should be quickly estimates sot the final preliminary weight estimate can more closely reflect the proposed ship design weight as constructed. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1192/buy}, author = {Hogg, W A G and Dominick Cimino} } @conference {1198, title = {1198. A Statistical Examination of Weight and KG Margin Values for U.S. Navy Surface Ships}, booktitle = {36th Annual Conference, San Diego, California, May 9-12}, year = {1977}, month = {5/9/77}, pages = {31}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {San Diego, California}, abstract = {Effective weight and KG (height of vertical center of gravity above the keel) margins are an essential element of the U.S. Navy Weight Control Program. Margins are not only an engineering tool for making technical prediction, but are embodied in the fiscal processes as well. The need for improvements in margin determination was recognized when the weight control program was formulated in 1961. The first improvements came with establishment of a formal margin policy in 1963. The values, restricted only to weight at that time, reflected the best corporate engineering judgment based on scattered and, in many cases, unverified weight growths. Because the shipbuilding process is relatively slow (compared to aircraft, land vehicles and missile production), it has taken fifteen years to accumulate a data based considered reasonable for a statistical study of margins. The data used in this paper are the product of the weight control program margin accounting system and represent a substantial improvement over the data used in 1963. This paper discusses the derivation of the data and the selection of appropriate statistical methodology in order to update the existing weight margin policy and establish a KG margin policy. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1198/buy}, author = {Straubinger, E K and Kern, P H} } @conference {1115, title = {1115. Marginal Cost Factors for Surface Combatant Ships}, booktitle = {35th Annual Conference, Philadelphia, Pennsylvania, May 24-26}, year = {1976}, month = {5/24/76}, pages = {40}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Philadelphia, Pennsylvania}, abstract = {The concept of utilizing marginal cost factors to determine the overall ship impact of design features is examined. The assumption is made that the design parameters for a feature such as the addition of a piece of equipment can be broken down into requirements for weight, space, manning and electrical paper and that these requirements are linearly superimposeable. Marginal weight factors in terms of changes in ship displacement were generated utilizing a computerized ship synthesis model. The sensitivity of these marginal weight factors to variations in the size of the ship (3000 to 12,000 tons) and the magnitude of the design parameter variation was investigated. It was determined that the marginal weight variation were more a function of the ship geometry than ship displacement. Marginal weight factors varied significantly between volume and freeboard limited ships. The validity of utilizing marginal weight factors to predict the overall weight impact on a ship is confirmed through a comparison with weight impact predicted directly by the synthesis model. The two methods were found to agree within + or {\textendash} seven percent for armament systems. However, the marginal weight factored generated in this study provided a low prediction for electronic systems. The overall conclusion to the study was that the concept of marginal cost factors is valid for predicting the impact of design changes on naval ships. However, a considerable amount of work remains before the technique can be universally implemented through the design community.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1115/buy}, author = {Howell, J S and Graham, LCDR C} } @conference {1026, title = {1026. Procedure for Evaluating Stability Required for Emergency Undocking of Nuclear Submarines During Destructive Weather}, booktitle = {33rd Annual Conference, Fort Worth, Texas, May 6-8}, year = {1974}, month = {5/6/74}, pages = {1}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Fort Worth, Texas}, abstract = {I regret to inform you that S.A.W.E. Paper No. 1026 "Procedure for Evaluating Stability Required for Emergency Undocking of Nuclear Submarines During Destructive Weather",authored by Mr. R. L. Beach of Charleston Naval Shipyard, Charleston, South Carolina, was not cleared for public release. However,a copy of the paper is available for use within the U. S. Navy establishment. Requests should include demonstration of the "need to know, and be sent to Commander Charleston Naval Shipyard Charleston, South Carolina 29408 Contractors desiring a copy of the paper should make requests directly to their Navy Contracting Officer for verification of security clearance and "need to know". Sincerely yours, Department of the Navy Naval Ship Systems Command Washington, D.C.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1026/buy}, author = {Beach, R L} } @conference {1027, title = {1027. Weight Margins, A Design Parameter for Undersea Vehicles}, booktitle = {33rd Annual Conference, Fort Worth, Texas, May 6-8}, year = {1974}, month = {5/6/74}, pages = {11}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Fort Worth, Texas}, abstract = {Defined weight margins are relatively new to the submersible design field. They have come into general use only recently with advanced submarine designs. Weight margin refers to a design "tool" now attaining a high degree of sophistication, but often confusing to designers who have not been involved directly in a program of design weight control. Based on the premise that a technical paper is primarily an educational aid, the objective of this dissertation is to provide technical designers with a working knowledge of intricate margin effect computations. Also given is general background information on the development of margin to its present level of requirement in a submersible vehicle design package. Except for the section on computations, the material is presented in narrative form covering history, necessity, source, and amount. Included is a graphic representation of the classification of margin types into the four groups usually reported on current military submersible design controls. Security restrictions preclude reference to any specific defense design or contract, but historical backup for the statements in this paper exists in the record files of: (a) The Electric Boat division of General Dynamics, Groton, Connecticut (b) Supervisor of Shipbuilding, Conversion and Repair, USN, Groton, Connecticut The establishing of definite rules for the determination, allocation, and disbursement of weight margins has been deterred by an insufficiency of historical data. Weight control for submersible vehicles is a new technology that must be built up block by block on the firm foundation of experience.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1027/buy}, author = {Bellos, W T} } @conference {1028, title = {1028. Weight Control on a High Performance Craft}, booktitle = {33rd Annual Conference, Fort Worth, Texas, May 6-8}, year = {1974}, month = {5/6/74}, pages = {14}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Fort Worth, Texas}, abstract = {This paper describes the weight control program, and results, on a new high speed fast patrol boat,the Coastal Patrol and Interdiction Craft. The Coastal Patrol and Interdiction Craft, called CPIC, is a 100 foot, high performance combatant craft. Weight (and displacement) of combatant craft is critical to successful performance. The CPIC was designed to carry a specific weapon system and has a specific mission profile. Growth in displacement would seriously impact on the engine power required and impact on the size and cost of the craft. Differences in the design weight and construction weight estimates were sufficient to question the adequacy of the main propulsion system with regard to speed, endurance and the attendant engineering review became most significant. The weight control efforts and results are described with a general overview of the project. No contract requirements existed for stringent weight reduction performance. The methods by which control was developed on the existing contract are discussed, and observations provided for consideration in developing improved control methods. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1028/buy}, author = {Pike, J W} } @conference {1029, title = {1029. The Outlook for Lighter Structures in High Performance Marine Vehicles}, booktitle = {33rd Annual Conference, Fort Worth, Texas, May 6-8}, year = {1974}, month = {5/6/74}, pages = {12}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Fort Worth, Texas}, abstract = {Structural weights of existing high performance marine vehicles, principally hydrofoil craft, are examined to determine the design or geometric parameters that have significant effect. For total structural density are shown to be governing. Similarly, the governing parameters and the loads which determine scantlings, where known, are compared to develop measures of efficient use of structural material. These figures of merit are applied to a number of existing high performance marine vehicles and projections of what might be attainable in the future are made. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1029/buy}, author = {Heller, S R and Clark, D J} } @conference {1030, title = {1030. Advanced Composites and Their Application to Hydrofoils}, booktitle = {33rd Annual Conference, Fort Worth, Texas, May 6-8}, year = {1974}, month = {5/6/74}, pages = {15}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Fort Worth, Texas}, abstract = {Over the past 10 years, significant progress Following a brief review of the advanced composites and their application to structural components of aircraft, missiles, and space vehicles, studies are presented on potential applications of composites to various structural components of hydrofoils, including decking, hull, foils, and strut. It is shown that application of various composites to the hull and decking of a hydrofoil can yield a weight saving of 16 to 51 percent whereas application of composites to struts and foils shows potential weight savings of ~60 percent compared to steel counterparts. Results are also presented on cost effectiveness of composites as applied to hydrofoils. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1030/buy}, author = {Gresczuk, L B and Hawley, A V and White, T} } @conference {1031, title = {1031. Structural Weight Determination for SWATH Ships}, booktitle = {33rd Annual Conference, Fort Worth, Texas, May 6-8}, year = {1974}, month = {5/6/74}, pages = {14}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Fort Worth, Texas}, abstract = {This paper briefly describes a series of structural design and weight estimating procedures for SWATH ships. Since very little prior knowledge exists in the area of reliable prediction of applied loads, precise design procedures, and typical scantlings, studies were conducted to develop adequate structural design methods. These range In complexity from gross weight fraction approximation, to a volumetric density method, to an area density method developed for use in a SWATH Feasibility Synthesis computer program, and finally to a more detail structural design using a modified version of the computer program, Midship Section Design for Naval Ships. The effects on the structural weight of varying geometry, sea-induced loads, local loads, and of changing the primary construction material to other higher strength steels and/or aluminum alloys are presented. The assumed loads are cited, and the need for better local and overall load definition is discussed. Opinions of the merits and shortcomings of these procedures are given. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/1031/buy}, author = {Aronne, E L and Lev, F M and Nappi, N S} } @conference {0875, title = {875. Control of Marine Vehicle Weight by Applying the Proven Techniques of Aerospace Weight Control}, booktitle = {30th Annual Conference, Newport Beach, California, May 3-5}, year = {1971}, month = {5/3/71}, pages = {16}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Newport Beach, California}, abstract = {The products of the marine industry are among the most complex systems developed by man; they usually advance the state of the art and, more often than not, are produced under almost impossible schedule conditions. Shipbuilding today is encountering many of the problems which the aerospace industry faced a decade ago. Total package procurement, contract definition design techniques, multiple ship contracts, modular construction methods, assembly line fabrication and construction all reflect the change which is required by cost reduction, quicker delivery, and competition. Because under the new procurement system the contractor is responsible for total ships performance, it is necessary to use weight-control techniques to hold their weight to reasonable values. This paper will describe application of those techniques, with special emphasis on prediction and trend analysis. This is thought by the author to be one of the big weaknesses in present marine weight controls; weights are usually reported after the engineering design has been completed. This paper will also describe the metamorphosis of the people involved in marine weight control from a semi-technical clerical type to a full-fledged mass properties control engineer. Some companies may already utilize some of the techniques suggested by the author, and other companies may be in the most enviable position of not having a weight problem. This paper is written for consideration by those who are still searching for more positive control methods. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0875/buy}, author = {Lucero, L} } @conference {0876, title = {876. U.S.S. Morton (DD948) Weight Control - Construction Through Modernization}, booktitle = {30th Annual Conference, Newport Beach, California, May 3-5}, year = {1971}, month = {5/3/71}, pages = {16}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Newport Beach, California}, abstract = {This paper will trace the history of weight control and weight growth on the USS MORTON (DD948) from the time of her construction at Ingalls Shipbuilding Corporation (1957-1959), at Pascagoula, Miss., through an operational period from 1959 to 1969 and terminate with a detailed discussion of weight and moment control and reporting during her modernization at Long Beach Naval Shipyard from September, 1969 to September, 1970. The paper will discuss the various definitions of weight reports that were used during the initial design and construction of the ship. It will cover the methods used in reporting and controlling weight and moment during the service life of the ship. This involves many alterations accomplished through the use of shipalts. It will also cover the methods used by Type commanders to initiate alterations and the type of weight control that is applied to these alterations. The paper will deal with the use of the UNIVAC III computer at the Long Beach Naval Shipyard for weight control and reporting during the modernization phase of this ship{\textquoteright}s life. It will describe the method by which information is fed into the computer and how the tape program operates to turn out the completed product. The paper will illustrate the advantages to be gained by using the computer for weight and moment control, both in the accuracy gained, and the time saved. It is anticipated that the knowledge and experience gained by Long Beach Naval Shipyard, as delineated by this report, will assist other shipyards, both Naval and Commercial, in the performance of this task. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0876/buy}, author = {Levy, H} } @conference {0877, title = {877. Trend Analysis - Why and How}, booktitle = {30th Annual Conference, Newport Beach, California, May 3-5}, year = {1971}, month = {5/3/71}, pages = {31}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Newport Beach, California}, abstract = {This paper will discuss some of the basic philosophy behind and methods used in performing a trend analysis. Current problems associated with the management-weight control interface relative to trend analysis will also be discussed. Weight control personnel have a two-fold problem not significantly different from that of other professionals. Their problems are the selling of services while keeping abreast of the current technical knowledge. The tendency by management and weight control personnel to ignore new methods and functions of mass property analysis must be overcome if weight control is to survive. No professional can afford the luxury of not increasing his knowledge and capability. Research is a never ending task which always must be done in conjunction with a close scrutiny of pertinent information. An emphasis should be placed upon quality. In light of the current economic situation, weight control personnel must be more than clerks and calculators if their professional status is to be improved. One purpose of this paper is to give weight control personnel an approach which demonstrates to management the importance of an accurate and well-founded trend analysis. As presented, the trend analysis has six major components as follows: (1) Trending models (2) Historical data (3) Mass properties data base (4) Projected weight growth pattern (5) Potential changes (6) Predicted outcome All of these components have a role to play in the generation of a trend analysis. Special emphasis will be placed upon the mathematical aspect of trending models because this is normally the weakest link in the trend analysis process. There are many mathematical approaches available. Trending models developed from mathematical tool such as linear and non-linear maximum likelihood equations, adaptive Fourier exponential equations, asymptotic exponential equations, and polynomial regression analysis have been are currently being used. Due to time/space/presentation limitations, only the polynomial regression analysis and non-linear maximum likelihood equations will be developed relative to the mathematical trending curve procedures. A comparison of trending models and trend analyses at different time intervals in a design and production program will also be included. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0877/buy}, author = {Woelk, R A} } @conference {0860, title = {860. Merchant Ship Weight Estimation}, booktitle = {29th Annual Conference, Washington, D. C., May 4-6}, year = {1970}, note = {

L. R. "Mike" Hackney Award

}, month = {5/4/70}, pages = {43}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Washington, DC}, abstract = {

The estimation of the weights of the various parts of a ship is of major importance in a commercial shipyard for two reasons. They are one of the prime factors affecting the technical characteristics of the ship and they also form the basis for estimating the building cost of the ship. One would therefore expect that the derivation of accurate weights of ship parts would be a well ordered and almost mechanical procedure in every shipyard. However, although this may become so within the next few years with more and more familiarization and utilization of computers, it is not the case today. In fact, the methods used in some shipyards for the estimation of the steel weight and the weight of wood and outfit and, therefore, a major portion of the building cost would most likely surprise and even shock designers from other disciplines. Fortunately, these simple methods utilize data from similar types and sizes of ships and prove to be adequate as long as similar ships are being built. The trend today is toward new ship concepts and the existing simple empirical methods can therefore only be used for the purpose of preliminary design or "ball park" building cost estimates. This paper will attempt to show how the weights affect the overall design problem and to review the development of the better known existing empirical methods suitable for preliminary design. A method for preliminary design weight estimation, developed by the author some years ago, and a detailed weight estimation method which he has used, will also be described. Finally, some observations on the impact of computers to the problem of ship weight estimation will be offered.

}, keywords = {13. Weight Engineering - Marine, Mike Hackney Best Paper Award}, url = {https://www.sawe.org/papers/0860/buy}, author = {Lamb, T} } @conference {0862, title = {862. Another Look at the US Navy{\textquoteright}s Weight Control Program}, booktitle = {29th Annual Conference, Washington, D. C., May 4-6}, year = {1970}, month = {5/4/70}, pages = {10}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Washington, DC}, abstract = {The author discusses Shipbuilder and Design Agents response to the U.S. Navy Weight Control Program and the practical aspects of controlling weight growth on naval vessels. The application of weight control programs to defined classes of naval ships and suggested simplifications in certain areas is also discussed. The problems of recruiting and maintaining weight engineering personnel, and suggestions on the recording of weight data are also included in this paper.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0862/buy}, author = {Molloy, J C} } @conference {0863, title = {863. PERA and Weight Control}, booktitle = {29th Annual Conference, Washington, D. C., May 4-6}, year = {1970}, month = {5/4/70}, pages = {8}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Washington, DC}, abstract = {The PERA program was conceived by NAVSHIPS in 1966 as a plan of action to resolve the complex ship overhaul program. The objective of the PERA{\textquoteright}s is to assist NAVSHIPS and its field activities and the Fleet in efficiently and effectively accomplishing complex ship overhauls on schedule and within allocated funds. The program will provide the Fleet, upon completion of each overhaul and within specified funding and time constraints, a ship that is fully ready to carry out its mission. Weight control is an important feature in the PERA program. Most of the CVA{\textquoteright}s, DD{\textquoteright}s, DLG{\textquoteright}s and S8{\textquoteright}s are in status 2 stability wise so that weight control, not weight reporting must be exercised, The importance of weight control cannot be too strongly emphasized. At the present time a CVA cannot carry its required fuel oil because in full load the ship would exceed the limiting draft marks. DLG{\textquoteright} s undergoing AAW modernization are having ballast added so that the class may meet the required stability, list and trim requirements. DD{\textquoteright}s undergoing ASW modernization must have ballast added to also meet the required stability, list and trim requirements. At the present time the use of DISTILLATE fuel in lieu of the standard Navy fuel oil will also require the use of additional ballast. Predicated on the above it appears the PERA{\textquoteright}s have a very responsible role in the weight control program. When Class Improvement Plans (CIP{\textquoteright}s) are drawn up, a close watch must be kept on the weight and moment additions and what items must be removed to compensate for the additional weight and moment. There should be continual monitoring of weight control reporting and if necessary a preliminary inclining experiment conducted. The preparation of a PERA-supported 180 day letter requires accurate advance weight/stability data re: compensation and authorizing and defining the new ship portion of the industrial work package during the ship overhaul. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0863/buy}, author = {Chorley, J S} } @conference {0864, title = {864. Recurring Problems in Weight Reporting and Control}, booktitle = {29th Annual Conference, Washington, D. C., May 4-6}, year = {1970}, month = {5/4/70}, pages = {14}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Washington, DC}, abstract = {Typical problems in weight reporting .and control are described and illustrated with specific examples of their effects on the ships involved. It is shown that neglect of the weight control process can frustrate the intent of a shipbuilding program, resulting in the expensive production of ships which cannot perform their intended tasks, in some cases producing unsafe vessels. The effects of neglecting or postponing weight and moment calculations is illustrated by the British Hunt Class Escort Destroyers which were very seriously affected by overweight. The importance of proper organization and timely weight control action is illustrated by the United States DD409 Class Destroyers which had much the same experience. The necessity of clear responsibility for development of a design is illustrated by the United States Casco Class Monitors and the loss of HMS CAPTAIN. Both of which were built for their Navies without being fully designed or supervised by their Navy Departments. While the examples chosen are from the past, the principals they illustrate represent ever present pitfalls which can and will recur without intelligent weight control.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0864/buy}, author = {Egan, R S} } @conference {0750, title = {750. The US Navy{\textquoteright}s Weight Control Program 1961 - 1969}, booktitle = {28th Annual Conference, San Francisco, California, May 5-8}, year = {1969}, month = {5/5/69}, pages = {11}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {San Francisco, California}, abstract = {Since the inception of the Weight Control Program for Naval Vessels and the writing of reference (1), those engaged in shipbuilding for the U.S. Navy have witnessed a complete change in the techniques of weight engineering. With approximately eight years of experience in this endeavor by the Navy and private enterprise, much data has been accumulated as well as valuable experience gained. Based on this, the Navy should analyze it{\textquoteright}s Weight Control Program to determine those areas where improvements can be made. It would seem appropriate for the Navy to evaluate its{\textquoteright} Weight Control Program by posing certain questions such as the following: a) Is the cost to the government commensurate with the results? b) Is the Navy really controlling a ship{\textquoteright}s weight, KG, trim, list and margin during construction or overhaul as the program was designed to do? c) Are private shipbuilders, as well as the Navy{\textquoteright}s, doing everything within reason to further the cause of Weight Control? d) What is being accomplished by the Navy to educate its people connected with the program in regard to standardizing concepts used in negotiations with Contractors on Modifications, Accepted Weight Estimates and Government Furnished Material? e) What has or is being done to properly staff government activities and private contractors to accomplish the Navy{\textquoteright}s goals as set forth in detail specifications? NAVSEC has the Navy{\textquoteright}s complete history of Weight Control to date and the sole capability of re-evaluating the program, therefore it is impossible for the writer to answer the above questions. However, these questions are suggested and the following comments are made for the purpose of provoking thought in regard to improving the program as now delineated by detail specifications. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0750/buy}, author = {Smith, C F} } @conference {0751, title = {751. The Implementation of Weight Estimating and Weight Control Programs}, booktitle = {28th Annual Conference, San Francisco, California, May 5-8}, year = {1969}, month = {5/5/69}, pages = {31}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {San Francisco, California}, abstract = {In the early sixties, the U.S. Navy established weight requirements which differed substantially from previously used practices. By means of a Contractors Design Weight Estimate and a negotiated and agreed upon Accepted Weight Estimate the Shipbuilder is contractually obligated thru a supplemental agreement to deliver the vessel with a displacement and vertical center of gravity which do not exceed the values of the Accepted Weight Estimate modified for contract modifications and weight and moment changes in the Government Furnished Material and within the limits of trim and list as given by the Contract Specifications. Furthermore, the Inclining and Accepted Ship Report is an INSURV item and if the limits of the adjusted Accepted Weight Estimate are exceeded the shipbuilder might have to take costly corrective action. As a result of the above requirements which are stated in detail in the General Specifications (1) and detail specifications, Shipyards have initiated Weight Control Programs during the Construction of Navy vessels and have extended their staffs engaged in Weight Engineering. The problems shipyards face in hiring specialists for unusual projects, building up large engineering staffs during peak periods and subsequent reduction during slack periods can be solved by reiteration of the engineering and drafting facilities offered by a Design Agent. A Design Agent such as the J.J. Henry Co. is engaged in the Design of ships for NAVSEC and ship owners and has performed detail engineering for a great number of private and Navy shipyards. Thru the years, extensive experience has been obtained in the area of weight estimating for many types of merchant and naval vessels. This experience is the subject of this paper with emphasis on the comparison of weight estimating for merchant vessels and the Navy Control procedures. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0751/buy}, author = {Gyswyt, K} } @conference {0752, title = {752. The Consequences of a Nonexistent Weight Control Program During Construction of a Deep Submersible}, booktitle = {28th Annual Conference, San Francisco, California, May 5-8}, year = {1969}, month = {5/5/69}, pages = {11}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {San Francisco, California}, abstract = {Virtually every marine vehicle built today, from the supertankers to the smallest amphibians, are plagued by weight growth problems during some parts of their construction. In some cases this weight growth is discovered early and corrected at minimum expense. All too often, however, weight growth goes undetected, or its significance is lost until too late when costly corrective measures are required to bring the craft within minimum requirements. This paper illustrates the effects of excessive weight growth on a small deep submersible, why this occurred, and makes recommendations as to avoiding excess weight problems on future marine projects. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0752/buy}, author = {Williams, R E} } @conference {0753, title = {753. Service Life Weight Control for Naval Ships}, booktitle = {28th Annual Conference, San Francisco, California, May 5-8}, year = {1969}, month = {5/5/69}, pages = {17}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {San Francisco, California}, abstract = {In recent years, weight control for naval ships has become an accepted norm in maintaining required naval architectural limits for new construction and major conversions. However, there is no parallel effective control program to maintain these limits throughout the service life of the ship. The basic program now in effect consists primarily of weight reporting and compensation. It is, in general, dependent upon {\textquotedblleft}ball park{\textquotedblright} alteration estimates, the inclining experiment, careless weight reporting and inadequate reporting requirements. Weights, for alterations accomplished by forces afloat and by shipyards between overhaul periods, are often not reported. For scheduled overhauls, actual determinations of the weight and moment growth usually occurs after accomplishment or too late in the overhaul sequence to be an effective control parameter. Consequently, the present program, instead of controlling vertical moment and displacement growth is primarily an {\textquotedblleft}after the fact{\textquotedblright} compensation for this growth. The present program was established by a number of separate and often uncorrelated publications. These publications are briefly reviewed with appropriate comment as to their requirements and effectiveness. Emphasis is placed on these publications as they relate to the difficulty of the overhaul activity, the design activity, the Naval Ship Systems Command (NAVSHIPS), and forces afloat in maintaining an effective control program. The necessity of an effective control program during conceptual development, during detail design and during installation is discussed. A modified program building on some of the present requirements is advanced. Among the various points discussed are: unification of the publications pertaining to the program, determination of the stability base with a prorated service life weight and moment margin allocation, determination of the effect of alterations prior to detail design and verification of preliminary weights. The overall NAVSHIPS responsibility for coordination, control and education that is necessary for an effective control program, is stressed. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0753/buy}, author = {Beach, R L} } @conference {0754, title = {754. Weight Engineering in the Design of Sealab III Habitat}, booktitle = {28th Annual Conference, San Francisco, California, May 5-8}, year = {1969}, month = {5/5/69}, pages = {21}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {San Francisco, California}, abstract = {The SEALAB III habitat is a submersible vessel in which several deep sea divers can live for extended periods of time on the ocean bottom. It is non-propelled and contains an internal atmosphere pressurized to equal the external sea pressure. This pressure-equalization enables the divers to open the bottom hatches, thereby allowing free access to and from the submerged habitat. This paper describes how the design of the SEALAB III habitat has been influenced by weight engineering. It describes the habitat{\textquoteright}s self-leveling system as well as the variable and fixed ballast systems of the craft. Although the customary concept of weights in design is that of weight control and particularly weight reduction, the SEALAB craft design includes an unique need for additional weight without a corresponding increase in buoyancy. These and other features, including the method of predicting and estimating weights of prototype equipment, combine to show the key role that weight engineering has played in the design of the SEALAB III habitat. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0754/buy}, author = {Sowar, D} } @conference {0785, title = {785. Weight Distribution Requirements for Modular Ship Construction in the Preliminary Design Phase}, booktitle = {28th Annual Conference, San Francisco, California, May 5-8}, year = {1969}, month = {5/5/69}, pages = {16}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {San Francisco, California}, abstract = {The competitive nature of the total package concept presently used by the Navy for procuring ships has increased in number and complexity the problems faced by today{\textquoteright}s ship builders. In order to compete effectively, the ship builder must be able to develop the optimum design from the standpoint of performance, procurement cost, and life cycle cost and must be able to prove to the Navy{\textquoteright}s satisfaction that this has been accomplished. As a result, the ship builder must improve and optimize design and production techniques. Examples are the ship designers{\textquoteright} new and almost complete reliance on high speed electronic data processing equipment and, in production, the construction of ships by modules. The construction of ships by modules introduces the problem of three dimensional mass distribution of the ship components. This paper presents a three dimensional mass distribution technique and explains how this gives the weight control engineer the capability to respond to questions concerning weight distribution in a minimum of time and with a maximum of flexibility and accuracy. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0785/buy}, author = {Wood, N L and Mead, C M} } @conference {0666, title = {666. The Importance of Weights in Small Craft Design and Construction}, booktitle = {27th Annual Conference, New Orleans, Louisiana, May 13-16}, year = {1968}, month = {5/13/68}, pages = {8}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {New Orleans, Louisiana}, abstract = {The use of weights in small craft is a tool in a field that is still largely an art rather than a science. Weights have been known and used in the design and in the construction of vessels since the beginning of construction. Because of the physical size of the business enterprises, the weights must do more than merely determine centers of gravity and overall weight. They must and should beused as a means of determining cost and as a means of interpolating and extrapolating in preliminary design. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0666/buy}, author = {Colvin, T E} } @conference {0669, title = {669. Life Cycle Economic Considerations for Weight Changes to Naval Ships}, booktitle = {27th Annual Conference, New Orleans, Louisiana, May 13-16}, year = {1968}, month = {5/13/68}, pages = {38}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {New Orleans, Louisiana}, abstract = {One major factor that must be considered during ship system life cycle analysis is thettribute of weight changes. This weight factor includes, by definition, the additional consideration for th eeffects on volume. The quantification of weight changes for commercial merchant ship design is logically correlated to revenue earning payload. With due respect to the problem of trade route forecasting, the identjty of revenue factors for our commercial endeavors are by necessity far more finibe than those available for use in analyzing our military systems. (References (1) through (5)). In fact, there are those who question the place for economic considerations in the design selections of military systems. This paper is predicated on the basis that a resource tree with an unlimited output does not exist and the selections made for final military ship systems design must include economic considerations. The immediate goal of thi spaper is to stimulate additional thought in regards to methods and procedures that should be used in economically appraising the effects of weight changes to Naval ship systems. Review and discussion are encouraged with the sincere hope tha tthis will create improved techniques whereby the true value of weight changes for the anticipated life cycle of ship{\textquoteright}s systems can be realistically evaluated. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0669/buy}, author = {Holdridge, T E and Sias, P M and Moore, R G and Snyder, R C} } @conference {0670, title = {670. Determination of Weight, Volume, and Construction for Tankers and Dry Cargo Ships}, booktitle = {27th Annual Conference, New Orleans, Louisiana, May 13-16}, year = {1968}, note = {

L. R. "Mike" Hackney Award

}, month = {5/13/68}, pages = {163}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {New Orleans, Louisiana}, abstract = {

This paper presents a method, working charts, and substantiating data for obtaining selected design characteristics, component weights, functional volumes, and cost of construction of dry cargo ships and tankers. The method is substantially less time-consuming than the usual detailed ship design approachand is suitable for computer studies ofselected cases such as may be necessary in trade-off analyses. RAND Memorandum RM-3318-PR** dealt with these types of ships on a simplified basis, using the Maritime Administration{\textquoteright}s weight and cost grouping system. This paper usesthe Navy weight and cost grouping system, and the data base has been expanded in quantity and detail of information. To develop the method and thedata, details ofcomponent weights and costs of a numberof ships were obtained from various sources. Distribution of volumes by functions were calculated from such information as boolets of plans and Bonjean{\textquoteright}s curves. All of these data were analyzed and plotted in parametric form. Since the Navy system of grouping weights and costs was selected as the basis for all analyses, the data were reclassified from the familiar Maritime Administration 180-item weight system to the Navy 140-item weight system. The generally accessible weight information is usually published in the 3-component Marad or 7-component Navy system. Working charts showing the relationships of component weights, volume, material cost and man hours for the respective Navy weight and cost groups are presented in the body of the report. Substantiating data for these working sheets are presented in the appendixes ,which show the datapoints for the ship cases analyzed, and the rationale for determining the parametric relationships. The method presented in this paperis not intended to supplant the lengthyand more accurate methods employed by ship designers in preparation of designs or bids, but rather to provide a tool of first-order accuracy that will give quick solutions to those who must make dozens or even hundreds of ship design cases in the course of preparing a study. The method is useful to ananalysis of the effect on overall ship design of changing any, or several, parameter(s),e.g., propulsion type, hence weight ands peed, for a given value of power. It is {\textquoteright}also useful to the system analyst to whom the ship characteristics and cost are but one of many essential inputs.

}, keywords = {13. Weight Engineering - Marine, Mike Hackney Best Paper Award}, url = {https://www.sawe.org/papers/0670/buy}, author = {Johnson, R P and Rumble, H P} } @conference {0673, title = {673. Proposed Weight Control Program for Navy Ships}, booktitle = {27th Annual Conference, New Orleans, Louisiana, May 13-16}, year = {1968}, month = {5/13/68}, pages = {10}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {New Orleans, Louisiana}, abstract = {Current weight control programs appear to have one basic failure in that they tend to report weight rather than control it. This is true today despite specification requirements in current Navy contracts making the contractor responsible for delivering the completed ship within specified limits of weight and KG. Contractors are reluctant to spend money for weight control program unless it appears that the agreed upon limits will be xceeded. By the time weight reports have established this trend, the ship is well along in the construction stage and corrections are costly and often cause delays in delivery. This paper proposes a weightc ontrol program based on continual updating of the design weight estimate using information provided by the engineers and designers as they develop the detail design. Proposed changes from contract guidance plan concepts can be quickly estimated and their effect on weight and KG established prior to any appreciable work on the part of the contractor. Weight estimates fore lectrical, piping and ventilation systems would be based on diagrammatic plans prepared by the engineering sections. Comparison with the Accepted Weight Estimate would establish adverse trends prior to the preparation of working plans and the ordering of material. By having this type of knowledge available early in the design stage, the weight engineers together with the design engineers can effect true weight control.}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0673/buy}, author = {Ford, R G} } @conference {0600, title = {600. Weight Control Program Involving Overhauls and Conversions of Naval Vessels}, booktitle = {26th Annual Conference, Boston, Massachusetts, May 1-4}, year = {1967}, month = {5/1/67}, pages = {10}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Boston, Massachusetts}, abstract = {Major overhauls and conversions of United States Naval vessels, currently being undertaken and others in the planning stage, will confront weight engineers with a variety of problems. Most apparent of these will be that of meeting the weight control requirements, now included in contracts and specifications in the design, overhaul and conversion phases. Por most of us, it will make it necessary to revise and improve our ship weight control programs. In order to accomplish that objective, it Is the goal of this paper to present and discuss a timely and effective program for design and shipyard activities to consider. Experience has shown that weight control procedures, used for new construction of ships, are not directly extendable to an overhaul or conversion program. There is an apparent need for weight studies to be accomplished by the design or overhauling activity, sufficiently In advance of the start of the overhaul, to permit Its orderly review and assessment. Maximum use is to be made of existing design studies for similar tasks already completed or made available from other yards. The importance of assigning experienced personnel for a more accurate inventory and assessment of the ship, throughout the overhaul or conversion period, cannot be overemphasized. Among the subjects discussed are: 1) The events leading to the present control requirements 2) General approach to weight control 3) Design agent{\textquoteright}s weight estimate 4) Weights on working plans 5) Where the emphasis of weight control is to be applied 6) The degree of material and component weighing 7) Special weight problems 8) Communication 9) Report generation It may be concluded that the weight engineer{\textquoteright}s struggle to influence others of the importance of weight control continues. Assistance is still needed to accomplish the mutual objective of delivering a most satisfactory ship that meets requirements and has the potential for future improvements. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0600/buy}, author = {Kalafarski, C P} } @conference {0601, title = {601. The Responsibilities of the Supervisor of Shipbuilding, Conversion and Repair, U.S.N., Newport News, Virginia, for the US N}, booktitle = {26th Annual Conference, Boston, Massachusetts, May 1-4}, year = {1967}, month = {5/1/67}, pages = {12}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Boston, Massachusetts}, abstract = {Many newly constructed, converted or overhauled ships have exceeded design limitations of displacement, KG, stability, trim and list. Therefore, the Navy has developed a weight control program for U.S. Naval ships. This paper describes the implementation of the Supervisor{\textquoteright}s policy of preventing, unacceptable weight and/or moment growth of ships, and responsibilities therein, under cognizance of this office. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0601/buy}, author = {Smith, C F} } @conference {0602, title = {602. Use of Weight Control and Total Life Cycle Cost-Effectiveness Analysis for Merchant Ship Design}, booktitle = {26th Annual Conference, Boston, Massachusetts, May 1-4}, year = {1967}, month = {5/1/67}, pages = {35}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Boston, Massachusetts}, abstract = {Weight control and total life cycle cost-effectiveness should become basic considerations for future merchant ship design, construction and operation. These considerations, if properly applied, could improve overall performance, increase stability, and provide more potential dollar return for initial investments. The evaluation of these elements should commence in the original concept phases and continue throughout the detail design and construction periods. To achieve the greatest benefits, new design concepts must be considered on a total expected life cycle basis taking into consideration tradeoffs between initial costs and in-service performance. The above program is considered a mandatory prerequisite to improving the position of the United States Merchant Marine in providing systems and ships that will perform at competitive rates. Further, these techniques are basic tools that must be applied if the total system concept to develop prototype commercial maritime transportation systems such as proposed in reference (1) is to be successful. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0602/buy}, author = {Holdridge, T E and Sias, P M} } @conference {0604, title = {604. Weight Control for Commercial Ship Design and Construction}, booktitle = {26th Annual Conference, Boston, Massachusetts, May 1-4}, year = {1967}, month = {5/1/67}, pages = {17}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Boston, Massachusetts}, abstract = {Naval architects and shipbuilders consider weight estimation as one of the most important design considerations in the preparation of the design and construction of a ship. The naval architect generally proceeds through three steps in the design of a ship with a weight estimate prepared during each phase. The completeness of the weight estimate increases during the design process from an estimate based on experience and/or established factors to an estimate based on plans and specifications. From this point on the shipbuilder carries on the weight estimate in much greater detail. The weight estimate is a tool for the designer and builder and is of no interest to the prospective ship owner except as it influences future revenues of the vessel. The method of weight estimation is uniform throughout the world with greater emphasis being placed on it if Government assistance is required for construction funds. Due to the fact that ship designing and construction would be pure guesswork without a weight estimate, it is mandatory that well-trained and qualified engineers and technicians participate in this facet of the shipbuilding program. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0604/buy}, author = {Adair, L P} } @conference {0605, title = {605. How Much Weight Control of Aircraft Carriers?}, booktitle = {26th Annual Conference, Boston, Massachusetts, May 1-4}, year = {1967}, month = {5/1/67}, pages = {19}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Boston, Massachusetts}, abstract = {Weight control of an aircraft carrier for the shipbuilder begins with the Preliminary Design Weight Estimate and may possibly end with the acceptance of this estimate. However, if sufficient margins have not been provided to compensate for the weight and moment increases which may occur during design and construction, the shipbuilder may be confronted with the impossible task of delivering the ship within the accepted weight and KG* limits. Unpredicted KG rise occurring during the inclining experiment must be recognized by the ship{\textquoteright}s owner and the builder must be permitted to compensate for this rise with vertical moment margin. Early in the detail design of a carrier a comparatively small amount of weight control is possible. However, by the time a definite trend appears violating the limits of the weight control contract, design and construction will have progressed to the point that only anticipated margins in the Accepted Weight Estimate will compensate for delivery of the ship within the limits. If the inclining experiments are to be the final determination for acceptance of the end product, improvements are needed in the state of the art. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0605/buy}, author = {Lake, B M} } @conference {0606, title = {606. Application of Electronic Data Processing Techniques to Weight Control of Naval Vessels During the Detail Design and Constr}, booktitle = {26th Annual Conference, Boston, Massachusetts, May 1-4}, year = {1967}, month = {5/1/67}, pages = {41}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Boston, Massachusetts}, abstract = {Weight Control as applied to naval shipbuilding should accomplish exactly what the name implies; {\textquotedblleft}Control of Weight.{\textquotedblright} In many instances however, weight control procedures have been only marginally successful due to the lack of methods and manpower necessary to cope with the constantly changing effects of contract modifications, design developments, and various other complicating factors. In order to better maintain control of weight data during this critical period, quite a number of ship design and construction facilities have adopted electronic data processing techniques. Many of the {\textquotedblleft}computerized{\textquotedblright} weight control systems now in use however, are in actuality automated hand calculations and make use of the computer only as a semi-automatic printing device. This approach is often more costly than hand methods and although same time can be saved, the weight engineer may have even less control over weight data due to the extra steps involved. What is needed is a whole new approach to the weight control problem utilizing electronic data processing as a fundamental tool. Procedures must be established that will integrate weih1 control with other allied areas such as plan scheduling and development, material take-off, change order negotiation, and quality assurance. Programming a computer to Co the total job of weight control is practical only after the desired goals have been more concretely defined. This paper discusses some of those ambiguous areas (at least to a computer{\textquoteright}s way of {\textquotedblleft}thinking{\textquotedblright}) encountered while writing a series at {\textquotedblleft}weight engineer oriented{\textquotedblright} programs for a small scale digital computer. A system that has been established to help integrate weight control with the rest of the design effort is described along with other suggestions for the preparation, manipulation, and extraction of the data needed for the weight engineer to indeed maintain {\textquotedblleft}control of weight{\textquotedblright}. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0606/buy}, author = {Storie, J M} } @conference {0463, title = {463. Weight Engineering and Ship-Building}, booktitle = {23rd National Conference / Sheraton, Dallas Hotel, Southland Center, Dallas, Texas May 18-21}, year = {1964}, month = {5/18/64}, pages = {18}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Dallas, Texas}, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0463/buy}, author = {Weiler, D J} } @conference {0303, title = {303. Some Aspects of Weight Engineering as Applied to Marine Vehicles}, booktitle = {21st National Conference, Seattle, Washington, May 14-17}, year = {1962}, month = {5/14/62}, pages = {13}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {13. WEIGHT ENGINEERING - MARINE}, address = {Seattle, Washington}, abstract = {This paper was presented at the Annual National Conference of the Society of Aeronautical Weight Engineers at Seattle, Washington, May 14-17, 1962. With the requirement of overall speed increase for marine vehicles, it appears that hydrofoil supported vehicles and the air cushion vehicles are the two most logical candidates to meet this requirement. Because the design of these two vehicles requires the use of principles that are well understood by the designers of aircraft, it is believed that the aircraft industry can contribute to, and hasten the development of such vehicles. This paper evaluates the importance for weight engineering and cites the recognition of the problem of weight and balance control by the U.S. Navy, Bureau of Ships as support to this theory. A suggested list of technical objectives and areas of responsibilities for weight engineers working in the marine vehicle design field is presented. Several examples of the type of weight trade studies that can be made by the weight engineer are presented. The potentials of weight reduction are demonstrated by quoting some examples from a weight reduction study made by the Advanced Marine Systems Weight Group of the Boeing Company. This paper suggests that he weight engineer can increase his effectiveness and broaden the weight engineering profession by accepting responsibilities that were formerly treated only by naval architects. }, keywords = {13. Weight Engineering - Marine}, url = {https://www.sawe.org/papers/0303/buy}, author = {Dyer, J W} }