Flight director guidance throughout the parabolic maneuver

The high precision required to maintain constant acceleration during the parabolic micro-gravity condition makes the pilot´s control task difficult: the optimization of the duration requires an accurate entry into the parabola at the right moment, while the aircraft limitations may not be exceeded. To resolve this problem, flight director control laws incorporating a gain scheduler, a predictor, and a sequencer have been developed to improve the quality and duration of the parabolic maneuver and to increase the safety by monitoring the progress of the maneuver. A flight simulation program was then used to evaluate the flight director system in a fixed-based simulation, and to train the test pilot. Finally, the flight director was evaluated during flight tests with the laboratory aircraft. A considerable improvement to maintaining the precision of micro-gravity conditions was obtained. The development and design of the flight director system, as well as its experimental evaluation, are discussed