The Messerschmitt Bf 109, often called Me 109, was a German World War II fighter aircraft designed by Willy Messerschmitt and Robert Lusser during the early to mid 1930s.It was one of the first truly modern fighters of the era, including such features as all-metal monocoque construction, a closed canopy, a retractable landing gear, and was powered by a liquid-cooled, inverted-V12 aero engine.