Stearman Senior Speedmail
The Stearman Model 4 was a commercial biplane built by the Stearman Aircraft Company at Wichita, Kansas, first flown in 1929. Its two-seat versions were Junior Speedmails and its single-seat mailplanes Senior Speedmails; fast and strongly built, the type served airlines and oil-company fleets, and only forty were built. Survivors still fly in private hands, and several are preserved in museums.