|Role||three-seat light commercial biplane|
|National origin||United States|
|Status||a few are still airworthy|
|Primary user||air mail and commercial companies|
The C3 was a rugged biplane with simple straight wings, a tough undercarriage with oleo shock absorbers and two open cockpits with the pilot in the rear and two side-by-side passenger seats in the front. In fact, it was a slightly modified version of the earlier model C2 aircraft. Changes included an increased volume oil tank and larger sized baggage compartment.
Introduced in 1928, the C3 was powered by a variety of engines of between 128 hp and 225 hp, each version having its own designation. The last version of the C3 was the C3R which had several external differences including a cutout in the aft portion of the wing center section for improved pilot visibility, a headrest in the aft cockpit, and slightly increased chord of the rudder and vertical stabilizer.
Although there were several versions of the C3, most were either the C3B and the C3R. A few C3s were approved for float operations.
The C3 was built with light commercial applications in mind, including passenger flying and business flights. The C3MB was a special mail-carrying aircraft based on the C3 with the forward cockpit enclosed as a dedicated cargo compartment. This version was operated in 1928 by National Parks Airways on airmail route CAM 26 from Salt Lake City, Utah to Pocatello, Idaho and Great Falls, Montana.
- First of the C series powered by a Curtiss OX-5, later re-engined with a 240 hp (179 kW) Menasco-Salmson radial as the C1X. One built.
- Four aircraft similar to the C1, with the radiator mounted underneath, hydraulic shock absorbers and dual controls. Variously powered by 90 hp (67 kW) Curtiss OX-5, Wright-Hisso A, Wright Whirlwind and Menasco-Salmson radial engine.
- C3B Sport Commercial
- 220 hp (164 kW) Wright J5 radial engine.
- 150 hp (112 kW) Wright Martin/Hispano Suiza E engine.
- 180 hp (134 kW) Wright Martin/Hispano Suiza E engine. 1 delivered.
- 190 hp (142 kW) Wright Martin/Hispano Suiza E2 engine
- 190 hp (142 kW) Wright Martin/Hispano Suiza E3 engine.
- 190 hp (142 kW) Wright Martin/Hispano Suiza E4 engine.
- 260 hp (194 kW) Menasco-Salmson air-cooled engine.
- 160 hp (119 kW) Curtiss C6 engine.
- 128 hp (95 kW) Siemens-Halske Sh 12.
- 130 hp (97 kW) Comet 7D radial engine. 1 built, later converted to C3B.
- C3B with forward cockpit enclosed for mail carrying.
- 220 hp (164 kW) Wright J5 Whirlwind radial engine.
- C3R Business Speedster
- 225 hp (168 kW) Wright J6.
Aircraft on display
- Crew: 1
- Capacity: 2 passengers
- Length: 24 ft 0 in (7.32 m)
- Wingspan: 35 ft 0 in (10.68 m)
- Height: 9 ft 0 in (2.75 m)
- Empty weight: 1,650 lb (748 kg)
- Useful load: 1,025 lb (465 kg)
- Max. takeoff weight: 2,650 lb (567)
- Simpson, 2001, pp. 520–521.
- Davies 1998, p. 142.
- Eckland, E.O. "Stearman". aerofiles.com. Retrieved 27 December 2018.
- Grey, C.G., ed. (1931). Jane's all the World's Aircraft 1931. London: Sampson Low, Marston & company, ltd. pp. 317c–318c.
- Museum of Flight. "Stearman C-3B - Manufacturer was Stearman Aircraft Company". Museumofflight.org. Retrieved 2012-07-21.
- Ken Olsson. "Our Stories". Waaamuseum.org. Retrieved 2012-07-21.
- Simpson 2001, p. 521.