The Kaydet, the two-seater biplane introduced by Stearman Aircraft Division of Boeing in Wichita, Kan., 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 for novice pilots for the U.S. Army Air Corps (PT-13/-17) and U.S. Navy (NS/N2S - pictured here).