Flight -Test Evaluation of Stability Augmentation Steering System for Aircraft Ground Handling

A flight-test program was conducted to evaluate a newly developed stability augmentation steering system (SASS). Designed to improve the ground-handling characteristics of a U.S. Navy jet trainer, the SASS features a yaw-rate feedback that is used to set the heading attitude bandwidth as desired, while providing an essentially constant rudder pedal sensitivity variation with speed. Flight-test efforts were conducted to assess performance of two SASS configurations against the baseline aircraft configuration. Three pilots evaluated the ability of the aircraft to perform a runway offset capture-and-hold maneuver, essentially a lane change task, with and without braking. The task with braking was found to be the better separator in terms of pilot ratings for the two SASS configurations when compared to the baseline aircraft. The flight-test program found that the SASS significantly improved the ground handling of the aircraft.