Boeing-Stearman Model 75
The Stearman (Boeing) Model 75 is a biplane formerly used as a military trainer aircraft, of which at least 10,626 were built in the United States during the 1930s and 1940s. Stearman Aircraft became a subsidiary of Boeing in 1934. Widely known as the Stearman, Boeing Stearman, or Kaydet, it served as a primary trainer for the United States Army Air Forces, the United States Navy (as the NS and N2S), and with the Royal Canadian Air Force as the Kaydet throughout World War II. After the conflict was over, thousands of surplus aircraft were sold  on the civilian market. In the immediate postwar years, they became popular as crop dusters and sports planes, and for aerobatic and wing walking use in air shows. Design and development. The Kaydet was a conventional biplane of rugged construction, with a large, fixed tailwheel undercarriage, and accommodation for the student and instructor in open cockpits in tandem. The radial engine was usually not cowled, although some Stearman operators choose to cowl the engine, most notably the Red Baron Stearman Squadron. Operational history. Post-war usage. After World War II, thousands of surplus PT-17s were auctioned off to civilians and  former military pilots. Many were modified for cropdusting use, with a hopper for pesticide or fertilizer fitted in place of the front cockpit. Additional equipment included pumps, spray bars, and nozzles mounted below the lower wings. A popular approved modification to increase the maximum takeoff weight and climb performance involved fitting a larger Pratt & Whitney R-985 Wasp Junior engine and a constant-speed propeller. Variants. "Data from:"United States Navy aircraft since 1911, Boeing aircraft since 1916 The U.S. Army Air Forces Kaydet had three different designations based on its power plant: The U.S. Navy had several versions, including: Surviving aircraft . A considerable number of Stearmans remain in flying condition throughout the world, as the type remains a popular sport plane and warbird. In popular culture. An iconic movie image is a Stearman cropduster chasing Cary Grant across a field in "North by Northwest" (the airplane that chased Grant was actually a Naval Aircraft Factory N3N Canary; the plane that hits the truck is a Stearman).