A Practical Approach to Enhance the Flight Endurance of a Fixed-Wing UAV

This paper presents a summary of research toward extending the flight duration of fixed-wing unmanned aerial vehicles at ADE. A historical context to extended flight is provided and particular attention is paid to research in establishing the best operating profile for the Reciprocating Piston engine to meet the extended endurance target. With the limitation of the fuel capacity in the UAV, it is imperative to identify and operate the UAV at the lowest fuel consumption regime without compromising the mission objectives. Usage of variable pitch propeller along with operation of mixture control of the engine has resulted in the extension of endurance of up to 12 h. Autonomous flying presents a unique set of challenges whereby the flight computer of the aircraft must command and control the engine to be operated at the best operating regime. The basic mechanisms of variable pitch propeller operation are examined. During the present work, automation tables were evolved to aid the flight control computer.