Exploration and mapping of an unknown flight envelope

The flight envelope of an aircraft consists of the constant trim states that the aircraft can attain, given in terms of airspeed, turn rate, and flight path angle. Flight trajectories typically consist of a sequence of trim commands with intermediate transitions. While the flight envelope of an aircraft is determined beforehand, it may change under off-nominal conditions due to damage or actuator failure. The goal of this paper is to investigate the ability of an adaptive control law to reach new trim states in the case where the flight envelope is totally unknown. Within simulation, this approach provides an alternative technique for mapping the flight envelope. For an aircraft in flight, this approach can be used to reach new trim states under envelope uncertainty, as may occur during off-nominal flight conditions.