The Messerschmitt Bf 109 was a German World War II fighter aircraft designed by Willy Messerschmitt in the early 1930s. It was one of the first true modern fighters of the era, including such features as an all-metal monocoque construction, a closed canopy, and retractable landing gear. The Bf 109 was produced in greater quantities than any other fighter aircraft in history, with a total of 33,984 units produced up to April 1945. Fighter production totalled 47% of all German aircraft production, and the Bf 109 accounted for 57% of all German fighter types produced.