Controllers and Control Insights for a Bio-Inspired Rotating Empennage Fighter Aircraft

One method to improve aerodynamic efficiency in fighter aircraft is to remove the vertical tail. Removing the tail, however, causes complications in terms of control. If the tail is allowed to rotate for control, multiple trim solutions arise, where traditional aircraft generally only have one trim solution for a given flight condition. In the present work various control methodologies are studied for controlling a rotating tail fighter aircraft. Through analyzing these controllers it is found that, without modifying the BIRE aircraft, some minimum amount of lift must be carried on the tail for control to be successful, given common handling qualities and maneuvering metrics for fighter aircraft. If the center of gravity is shifted 1 ft forward, acceptable control performance is achieved as evaluated from fighter aircraft performance metrics. Despite the increased lift carried on the tail with the center of gravity shifted forward, the BIRE aircraft has lower drag than the baseline aircraft over a significant portion of the flight envelope.