USAAC Trainers
Interest from the United States Army Air Corps followed. The Menasco engines proved unreliable, and instead Kinner radial engines were fitted. Aircraft were produced as the PT-16 (15 built), PT-20 (30 built), PT-21 (100 USAAF, 100 USN) and finally as the definitive PT-22 Recruit (1,298 built) ordered in 1941 as pilot training began its rapid expansion.
Ryan also pioneered STOL techniques in its YO-51 Dragonfly observation craft. Three prototypes were built, but no USAAF order came.
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