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.[1]
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.[2] 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.[citation needed]
Although there were several versions of the C3, most were either the C3B and the C3R. A few C3s were approved for float operations.[1]: 59, 198–199
Operational history
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.[3]
Variants
Data from:Airlife's World Aircraft,[2] Aerofiles:Stearman[4]
Variants produced were:
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.[4]