The model ‘O’ was designed by Robert Hall following the Stinson Company receiving a requirement for a military trainer from the fledgling Honduran Air Force in 1933. In a 90 day project the wings, tail, struts, and lnding gear of a Stnson SR reliant were married to a newly constructed fuselage, a new wing centre section replacing the space occupied by the cabin fuselage of the SR. This resulted in a two place open cockpit parasol that is flown from the front seat, it being the only open cockpit aircraft ever produced by Stinson.
Powered by a Lycoming R-680-4 the aircraft was capable of a maximum speed of 136 mph / 219 kph, cruised at 124 mph / 200 kph and had a range of 440 miles / 708 km.
First flying in May 1933, only ten model ‘O’s were originally manufactured 1933 and 1944. Five were sold to Honduras, three to China, and one to Brazil. The prototype, NX13817 (ATC 520), stayed in the US and ended up as an instrument trainer in Long Beach, California. It was then moved to Love Field in Texas when WW2 started and stricken from the FAA registry in 1945.
Replica:
Evergreen Aviation Services Stinson Model O Senior Trainer replica
Engine: 220hp Lycoming R-680-4
Wingspan: 39’11”
Length: 27’8″
Useful load: 710 lb
Max speed: 136 mph
Cruise: 122 mph
Stall: 50 mph
Range: 400-450 mi
Ceiling: 16,000′
Seats: 2
All Aero 