Automatic limiters in Air Force aircraft flight control systems

The author examines the use of automatic limiters in the flight control systems of three Air Force aircraft, the F-111, F-16, and B-1B, to increase their resistance to loss of control during maneuvering flight. The limiters provide maximum usable maneuver envelopes while avoiding undesirable or unsafe regions. They function reliably, repeatably, and rapidly without the pilot `getting in the loop´, allowing him to concentrate on his mission. The aerodynamics and flight control systems of three aircraft are discussed as well as the functions particular to each. The common characteristics of the three systems are summarized. Several issues related to the application of limiters to future aircraft are addressed, including aerodynamic modifications of aircraft, performance impacts, increased complexity, cost/schedule impacts, testing of aircraft, effect on design quality, and modeling