Flight Testing Total Energy Control Autopilot Functionalities for High Altitude Aircraft

In this paper the design and flight testing of a Total Energy Control System (TECS) autopilot for a High Altitude Long Endurance (HALE) aircraft is presented. Autopilot control for HALE aircraft is a well-fitting application for the TECS control strategy, as this enables energy-efficient, decoupled airspeed and flight path control with explicitly handling thrust limitation. To achieve a realistic validation of the controller before moving towards the integration on the HALE platform, the flight testing is carried out on a Cessna Citation passenger aircraft. It has been proven that the adjustments required to implement the control laws on the Cessna Citation passenger aircraft are minimal. This indicates that the Cessna Citation aircraft serves excellently as a hardware platform and can be utilized for the validation of flight control code integration and functionality. The results of the flight test are discussed, and insights gleaned for the future integration of TECS on the HALE aircraft are provided