Accession Number : ADA138269

Title :   Evaluation of a Digital Flight Controller for a Flexible-Fighter Aircraft,

Descriptive Note : Master's thesis,

Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING

Personal Author(s) : Hoffman,M L

PDF Url : ADA138269

Report Date : Dec 1982

Pagination or Media Count : 159

Abstract : This thesis evaluates the effect of a digital flight controller on a flexible-fighter aircraft (FFA) at 0.8 Mach at 30,000. The two maneuvers incorporated in this flight controller are the g-command pull-up and the pitch-pointing maneuvers. Using a control law based on the control system theory developed by Brian Porter, a digital flight controller is first designed for a rigid body aircraft, and is then used on the FFA. This thesis evaluates the effect of the controller for the rigid body design when used on the flexible-fighter. The results showed excellent performance by the FFA. The flexible-fighter model is based on the rigid body dynamics of the AFTI/F-16 combined with the first bending mode of a flexible aircraft. The bending mode of the FFA was selected to correspond to expected characteristics in a typical fighter aircraft. Incorporating a time delay in the controller to represent the expected microprocessor computational time delay did not significantly affect the simulation time response of either the rigid body or the FFA. The Neal-Smith criterion is used to determine the acceptance of the design by a pilot.

Descriptors :   *Flight control systems, *Jet fighters, *Flight maneuvers, Digital systems, Rigidity, Frequency response, Flexural properties, Transonic characteristics, Microprocessors, Delay, Input output models, Variables, Control theory, Multiple operation, High altitude, Turning flight, High acceleration, Bending, Angle of attack, Subroutines, Computer programs, Acceptability, Pilots, Theses

Subject Categories : Attack and Fighter Aircraft
      Flight Control and Instrumentation

Distribution Statement : APPROVED FOR PUBLIC RELEASE