Prediction of Pilot-Aircraft Stability Boundaries and Performance Contours

Control-theoretic pilot models can provide important new insights regarding the stability and performance characteristics of the pilot-aircraft system. Optimal-control pilot models can be formed for a wide range of flight conditions, suggesting that the human pilot can maintain stability if he adapts his control strategy to the aircraft's changing dynamics. Of particular concern is the effect of suboptimal pilot adaptation as an aircraft makes transitions from low to high angles of attack during rapid maneuvering, as the changes in aircraft stability and control response can be extreme. The effects of optimal and suboptimal effort during a typical "high-g" maneuver are examined, and the concept of minimum-control effort (MCE) adaptation is introduced. Limited experimental results tend to support the MCE adaptation concept.