Bücker Bü 133 Jungmeister
The Bücker Bü 133 Jungmeister is a German single-seat aerobatic biplane introduced by Bücker Flugzeugbau in 1935 as a single-seat development of the two-seat Bü 131 Jungmann. Its fabric-covered steel-tube fuselage and wooden wings carried a 160 hp Siemens Sh-14A radial in most production aircraft, and its agility made it the Luftwaffe's standard advanced trainer and a dominant competition aircraft of the 1930s and 1940s. Wikipedia puts production at around 250, including 52 licence-built by Dornier in Switzerland and 25 by CASA in Spain, and survivors remain popular with airshow pilots.