The SEV-3 was an all-metal cantilever low-wing monoplane powered by a nose-mounted 420 hp (313 kW) Wright J-6 Whirlwind radial engine. It had two cockpits in tandem, a forward cockpit for the pilot and a rear cockpit for two passengers, both with sliding canopies. It could either be fitted with twin amphibious floats which had main wheels fitted in the floats to allow it to operate from land, or with a fixed tailwheel undercarriage with the mainwheels enclosed in large fairings.[1]
The SEV-3 first flew as a floatplane in June 1933, demonstrating excellent performance as both an amphibian and a landplane.[2] It was built in small numbers mainly for export.
Alexander de Seversky standing before the SEV-3XAR, autumn 1934
An SEV-3 established a world speed record for piston-engined amphibians in 1933, and on 15 September 1935, a Wright Cyclone-powered SEV-3 set a record of 230 mph (370.8 km/h) which stood for 49 years. A landplane version was also developed with conventional landing gear.[3]
The design influenced a long line of Seversky and later Republic aircraft, eventually leading to the development of the P-47 Thunderbolt. A landplane version was used by the United States Army Air Corps as a basic trainer with the designation BT-8, 30 of which were ordered in 1935.[4] This proved grossly underpowered and was quickly replaced by the North American BT-9.[5]
Amphibian for the Colombian Air Force, six built (only delivered four to Colombia), with Wright Whirlwind engines.
BT-8
Landplane basic-trainer for the United States Army Air Corps, developed from SEV-3XAR. 30 built.
SEV-X-BT
multi-discipline trainer version of the BT-8 with retractable undercarriage. The sole SEV-X-BT lost in competition to the North American BT-9 and was reportedly scrapped for spares to service the Seversky 2PA.[8]
^Green, William and Gordon Swanborough. "The end of the beginning...The Seversky P-35". Air Enthusiast, Ten, July–September 1979, pp. 8–9.
^Davis, Larry. P-35: Mini in Action (Mini Number 1). Carrollton, Texas: Squadron/Signal Publications, 1994. ISBN0-89747-321-3, p. 4.
^Editors, "NEW PLANE FOR THE CHIEF OF THE AIR CORPS" Air Corps News Letter, Information Division, Air Corps, Munitions Building, Washington, D.C., 1 July 1936, Volume XIX, Number 13, page 12.
Green, William and Gordon Swanborough. "The End of the Beginning...The Seversky P-35". Air Enthusiast, No. 10, July–September 1979, pp. 8–21. ISSN0143-5450
Howson, Gerald. "A Seversky in the Spanish War". Air Enthusiast, No. 18, April–July 1982, pp. 32–36. ISSN0143-5450
Spain
Colombia
