1158. The Vehicle Design Evaluation Program – A Computer-Aided Design Procedure for Transport Aircraft

Paper

Abstract

The Vehicle Design Evaluation Program (VDEP) is a computer-aided design procedure that provides a vehicle synthesis capability for vehicle sizing, external load analysis, structural analysis, and cost evaluation. The vehicle sizing subprogram provides geometry, weight, and balance data for aircraft using JP, hydrogen, or methane fuels. It has an option of providing ‘first pass’ performance data or conducting a detailed mission and performance analysis. A mass distribution and moment of inertia analysis is also provided. The external loads subprogram provides a method for developing steady-state load distribution on preliminary aircraft components for specified airplane weights and load factors. The structural synthesis subprogram uses a multi-station analysis or aerodynamic surfaces and fuselages to develop theoretical weights and geometric dimensions. The parts definition subprogram uses the geometric data from the structural analysis and develops the predicted fabrication dimensions, parts material raw stock buy requirements, and predicted actual weights. The cost analysis subprogram uses detail part data in conjunction with standard hours, realization factors, labor rates, and material data to develop the manufacturing costs. The cost analysis integrates the detail part developed manufacturing cost with the total program costs, which includes tooling, engineering, and return-on-investment, based upon airline route structures to provide a complete cost analysis capability. The integrated multi-disciplined aspects of the computer-aided design procedure provides a preliminary design tool that is designed to evaluate and provide trade study data for commercial transport aircraft, multibodied aircraft, cargo aircraft using both JP and cryogenic fuels, and Air Force and Navy fighter aircraft.
Emphasis is placed on the conceptual and pre-design applications for evaluating overall design effects on subsonic commercial type aircraft due to parameter variations. Trade study results are included for a short-haul subsonic commercial aircraft flying a typical mission profile. The automated procedure operates in batch and interactive mode, and is currently in operation at the NASA Langley Research Center, Air Force Flight Dynamics Laboratory, Naval Weapons Center – China Lake Facility, and the General
Dynamics Fort Worth and Convair divisions.