An Investigation of the Relationship Between Take Off Gross Weight and Mission Requirements for Geometrically Optimized Aircraft.
Abstract
A study was performed to demonstrate the feasibility of using surface fit approximations in the mission analysis for future fighter aircraft. Dash Mach number (MACH), dash range (RNG), and internal payload (STR) were selected as mission variables and a mission space defined based on a simple latin square method. Wing loading (WOS), aspect ratio (AR) and aircraft thrust-to-weight ratio (TW) were selected as design variables and a design space defined based on a simple latin square method. The take off gross weight (TOGW), take off distance (DTO), and the landing distance (DLN) were determined by the use of a computer program which simulated the required mission for each design case. A regression analysis was performed on this data to obtain quadratic surface fit approximations for TOGW, DTO, and DLN in terms of the design variables WOS, AR, and TW. An unconstrained minimization of TOGW was performed for all missions using a conjugate gradient technique to determine the minimum TOGW within the design space and the corresponding values of DTO and DLN. Another regression analysis was performed on the results of the minimizations and the mission variable for specific missions to obtain quadratic surface fit approximations for TOGW, DTO, and DLN for optimum aircraft in terms of the mission variables MACH, RNG, and STR. It was concluded that these surface fit approximations in terms of the mission variables were sufficiently accurate for use in mission analysis and conceptual design studies. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1977
- Accession Number
- ADA055882
Entities
People
- Milford K. Greenway Jr
Organizations
- Air Force Institute of Technology