The Kaydet, the two-seater bipane Wichita introduced in 1934, became an unexpected success during World War II. Despite its almost obsolete design, its simple, rugged construction made it ideal as a trainer. The Kaydet originated at the Boeing Stearman facility in Wichita, KS as the Model 70 trainer. After testing the Model 70, the Navy ordered 61 aircraft as Model 73s, designated NS-1s. All Kaydets had fabric-covered wooden wings, single-leg landing gear, and an over-built welded steel fuselage. Subsequent Wichita Models 75 and 76 used Army designations PT-13, PT-17, PT-18, and PT-27 and the Navy designation N2S. Despite the variety of designations, there was little difference between the versions, except for a few airplanes sold to the Canadian Air Force that had cold-weather canopies over their cockpits. Kaydets were widely used airplanes. They were sold to Canada, China, the Philippines, Venezuela, Argentina, and Brazil for both military and civilian uses. Many were still in service in the early 1990s. Their slow, low-level flying capabilities made them particularly suitable for crop dusting and spraying.