High Quality Content by WIKIPEDIA articles! The aircraft diesel engine or aero diesel has not been widely used as an aircraft engine. Diesel engines were used in airships and were tried in aircraft in the late 1920s and 1930s, but never widely used. Its main advantage is its excellent specific fuel consumption and the somewhat higher density of its fuel, but these advantages have been outweighed by combination of its inherent disadvantages compared to gasoline-fueled or turboprop engines.