Preliminary flight test results of a fly-by-throttle emergency flight control system on an F-15 airplane

Abstract

A multi-engine aircraft, with some or all of the flight control system inoperative, may use engine thrust for control. NASA Dryden has conducted a study of the capability and techniques for this emergency flight control method for the F-15 airplane. With an augmented control system, engine thrust, along with appropriate feedback parameters, is used to control flightpath and bank angle. Extensive simulation studies have been followed by flight tests. This paper discusses the principles of throttles-only control, the F-15 airplane, the augmented system, and the flight results including actual landings with throttles-only control. Nomenclature CAS control augmentation system CG center of gravity DEEC digital electronic engine control EMD engine model derivative HIDEC Highly Integrated Digital Electronic Control HUD heads up display PCA propulsion controlled aircraft V airspeed, kts α angle of attack, deg γ flightpath angle, deg φ bank angle, deg

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