@conference {3328, title = {3328. Mass Properties In VTOL USV Conceptual Design Software, Part II: Estimationg Fuel Mass Prooerties}, booktitle = {64th Annual Conference, Annapolis, Maryland}, year = {2005}, month = {5/14/05}, pages = {19}, publisher = {Society of Allied Weight Engineers, Inc.}, organization = {Society of Allied Weight Engineers, Inc.}, type = {12. WEIGHT ENGINEERING - COMPUTER APPLICATIONS}, address = {Annapolis, Maryland}, abstract = {The determination of an aircraft?s mass properties is critical during its conceptual design phase. Obtaining reliable mass property information early in the design of an aircraft can prevent design mistakes that can be extremely costly further along in the development process. In this paper, a method for estimating the mass properties of liquid fuel in a tank that is suitable for conceptual design software is presented. The method calculates mass, center of gravity, and moments of inertia of the fuel at arbitrary tank fullness and rotation. The method is applied to polyhedral geometry, which in many cases is used to approximate NURBS (Non-Uniform Rational B-Spline) surface geometry. This type of approximate representation is typically available in design software since this geometric format is conducive to graphically rendering three-dimensional geometry. Results for an example case of a cylindrical fuel tank are presented.}, keywords = {12. Weight Engineering - Computer Applications}, url = {https://www.sawe.org/papers/3328/buy}, author = {Ohanian, John} }