The Reliant is a high-wing, fixed-tailwheel land monoplane powered with a variety of radial engines.^[1]

1,327 Reliants of all types were made from 1933 to 1941, in different models, from SR-1 to SR-10. The final commercial model, the Stinson Reliant SR-10, was introduced in 1938. A militarized version was first flown in February 1942 and remained in production through several additional versions (all externally identical) until late 1943 for the US and British armed forces.^{[citation needed]}

Reliant production can be broken into two distinct types – the straight-wing Reliants (all models up to SR-6) and the gull-wing Reliants (all models from SR-7 and after, including the militarized V-77/AT-19), with there being little in common between the two groups of types. The straight-wing Reliant has a wing of constant chord and thickness which is supported by two struts each side with additional bracing struts. In contrast the taper-wing Reliant has the broadest chord and thickness of the wing at mid-span, with the outer wing trailing edge heavily angled forward and a rounded cutout on the leading edge root, all supported by a single strut. The taper wing has a significant step up between the fuselage and the wing, and the changes in wing thickness gave it a distinct gull appearance from the front.^{[citation needed]}

The Reliant was used by the United States Army Air Forces in World War II as a utility aircraft, designated UC-81, and as trainer designated AT-19. The Royal Navy and Royal Air Force also used Reliants, for light transport and communication duties. After the war they were sold on the civilian market as the Vultee V-77.

The V-77 is a spartan version of the SR-10 with the 300 hp Lycoming R680-E3B, a single door on the left side and the traditional "bump" cowl was replaced with a simpler smooth cowl. Internal structure was beefed up significantly over the commercial models, and a distinctive triangle-shaped counterbalance was added to the rudder.^{[citation needed]}

All versions of the Reliant were powered with radial piston engines, and could be operated on wheels, floats and skis, and in the following configurations:^[2]

• Cargo
• Ambulance (two stretchers)
• Firefighting
• Photographic mapping

• SR Reliant: Powered by a 215 hp (160 kW) Lycoming R-680.^[3]
• SR-1: Powered by a 240 hp (180 kW) Lycoming R-680-2. Two built.^[4]
• SR-2: Powered by a 240 hp (180 kW) Lycoming R-680-7.
• SR-3: Similar to the SR-1, but with retractable undercarriage.
• SR-4: Powered by a 250 hp (190 kW) Wright R-760-E.
• SR-5: Powered by a 225 hp (168 kW) Lycoming R-680-4.
• SR-5A: Powered by a 245 hp (183 kW) Lycoming R-680-6.
• SR-5B: Powered by a 240 hp (180 kW) Lycoming R-680-2.
• SR-5C: Powered by a 260 hp (190 kW) Lycoming R-680-5.
• SR-5E: Powered by a 225 hp (168 kW) Lycoming R-680-4.
• SR-5F: Powered by a 250 hp (190 kW) Wright R-760-E.
• SR-6: Four-seat cabin aircraft, powered by a Lycoming R-680-6.
• SR-6A: Four-seat cabin aircraft, powered by a 225 hp (168 kW) Lycoming R-680-4.
• SR-6B: Four-seat cabin aircraft, powered by a 260 hp (190 kW) Lycoming R-680-5.

• SR-7: First gull wing series.
• SR-7B: Four-seat cabin aircraft, powered by a Lycoming R-680-B6. 47 built.^[5]
• SR-7C: Four-seat cabin aircraft, powered by a Lycoming R-680-B5. Three built.^[5]
• SR-8A: Five-seat cabin aircraft.
• SR-8B: Five-seat cabin aircraft, powered by a Lycoming R-680-B6.
• SR-8C: Five-seat cabin aircraft, powered by a Lycoming R-680-B5.
• SR-8D: Five-seat cabin aircraft, powered by a Wright R-760-E2.
• SR-8DM: Utility transport version of the SR-8D.
• SR-8E: Five-seat cabin aircraft, powered by a 320 hp (240 kW) Wright R-760-E23.
• SR-8DE: Utility transport version of the SR-8E.
• SR-9: 1937 series. Fitted with a curved windshield, unique to this series.^[6]
• SR-9A: Proposed version with Lycoming R-680-B4 engine. Unbuilt.^[6]
• SR-9B: Powered by a 245 hp (183 kW) Lycoming R-680-B6 engine. 35 built.^[6][7]
• SR-9C: Powered by a 260 hp (190 kW) Lycoming R-680-B5 engine. 65 built.^[6][7]
• SR-9D: Powered by a 285 hp (213 kW) Wright R-760-E1 engine. 22 built.^[6][7]
• SR-9E: Powered by a 320 hp (240 kW) Wright R-760-E2 engine. 43 built.^[6][7]
• SR-9F: Powered by a 450 hp (340 kW) Pratt & Whitney Wasp Junior. 34 built.^[6]
• SR-10

• SR-10B: Powered by a Lycoming R-680-D6. One built.^[6]
• SR-10C: Powered by a Lycoming R-680-D5 engine. 46 built.^[6]
• SR-10D: Wright R-760E-1 engine. 3 built.^[8]
• SR-10E: Powered by a Wright R-760E-2. 21 built.^[8]
• SR-10F: Powered by a Pratt & Whitney R-985 Wasp Junior SB. 18 built.^[9]
• SR-10G: Powered by a Lycoming R-680-E1. 12 built.^[6]
• SR-10J: Lycoming R-680-E3 engine. 11 built.^[6]
• SR-10K: Powered by a 450 hp (340 kW) Wright R-975E-3. 2 built for New York City Police Department; one with conventional landing gear, one seaplane with Edo floats.^[6][10]

AT-19

USAAF designation for a training variant of the UC-81 for the Royal Navy under Lend-Lease as the Reliant I, 500 built.^[11]

AT-19A

Original designation of the L-9A which was a Voyager not a Reliant.^[11]

AT-19B

Original designation of the L-9B which was a Voyager not a Reliant.^[11]

AT-19C

Conversions of AT-19s for photo-survey aircraft for the USAAF, 51 conversions.^[11]

UC-81

Four impressed SR.8Bs.^[13]

UC-81A

Two impressed SR.10Gs.^[13]

UC-81B

One impressed SR.8E.^[13]

UC-81C

Three impressed SR.9Cs.^[13]

XC-81D

One civil SR.10F operated by the military for the development of glider pick-up techniques.^[13]

UC-81E

Four impressed SR.9Fs.^[13]

UC-81F

Seven impressed SR.10Fs.^[13]

UC-81G

Three impressed SR.9Ds.^[13]

UC-81H

One impressed SR.10E.^[13]

UC-81J

Nine impressed SR.9Es.^[13]

UC-81K

Five impressed SR.10Cs.^[13]

UC-81L

Two impressed SR.8Cs.^[13]

UC-81M

One impressed SR.9EM.^[13]

UC-81N

Two impressed SR.9Bs.^[13]

L-12

Two SR.5As impressed into service with the USAAF during World War II.^[14]

L-12A

Two SR.7Bs impressed into service during World War II.^[14]

RQ-1

One SR-5 Reliant was acquired by the US Coast Guard in 1935, later redesignated XR3Q-1 and decommissioned in 1941.^[15]

XR3Q-1

One SR-5 Reliant was acquired by the US Navy in 1935.^[16]

Reliant I

500 Reliants were supplied to the Royal Navy under Lend-Lease. The Reliants were used for light transport and communications, navigation and radio training duties.

  Argentina

• Argentine Navy^[9]

  Australia

• Royal Australian Air Force – 1^[17]

  United Kingdom

• Royal Air Force
  • No. 510 Squadron RAF^[18]
• Fleet Air Arm
  • 730 Naval Air Squadron
  • 748 Naval Air Squadron

  United States

• United States Army Air Forces – A total of 47 Reliants impressed during World War 2^[19]
• United States Coast Guard^[15]
• United States Navy^[9]

  Uruguay

• Uruguayan Air Force^[20]

  Brazil

• Aerolloyd Iguassu
• Aerovias Minas Gerais
• NAB – Navegação Aérea Brasileira

  El Salvador

• Grupo TACA

  Mexico

• Aeronaves de México – the Reliant was the first aircraft used by Aeronaves, later to become Mexico's largest airline, Aeromexico, on their initial service between Mexico and Acapulco on 14 September 1934^[21]

  Norway

• Widerøe

  Paraguay

• Líneas Aéreas de Transporte Nacional (LATN)

  United States

• New York City Police Department Aviation Unit
• Northwest Airways

Data from General Dynamics Aircraft and their Predecessors^[9]

General characteristics

• Crew: one, pilot
• Capacity: 3 to 4 passengers
• Length: 27 ft 11 in (8.51 m)
• Wingspan: 41 ft 7 in (12.68 m)
• Height: 8 ft 6 in (2.59 m)
• Wing area: 256.5 sq ft (23.84 m²)
• Empty weight: 3,045 lb (1,384 kg)
• Gross weight: 4,605 lb (2,093 kg)
• Powerplant: 1 × Pratt & Whitney Wasp Junior SB nine-cylinder air-cooled radial engine, 400 hp (298 kW)

Performance

• Cruise speed: 154 kn (177 mph, 285 km/h)
• Range: 739 nmi (850 mi, 1,369 km)
• Service ceiling: 21,000 ft (6,400 m)
• Rate of climb: 1,330 ft/min (6.8 m/s)

Aircraft of comparable role, configuration, and era

• Cessna Airmaster
• de Havilland Canada DHC-2 Beaver
• Fairchild 24
• Howard DGA-15
• Monocoupe 90
• Noorduyn Norseman
• Waco Standard Cabin series

Related lists

• List of aircraft of the Fleet Air Arm
• List of aircraft of the Royal Air Force
• List of aircraft of the United States during World War II
• List of aircraft of World War II
• List of military aircraft of the United States
• List of United States Navy aircraft designations (pre-1962)

• Andrade, John (1979). U.S. Military Aircraft Designations and Serials since 1909. Midland Counties Publications. ISBN 0-904597-22-9.
• Elliot, Bryn (March–April 1997). "Bears in the Air: The US Air Police Perspective". Air Enthusiast. No. 68. pp. 46–51. ISSN 0143-5450.
• Halley, James J (1980). The Squadrons of the Royal Air Force. Tonbridge, Kent, UK: Air Britain (Historians). ISBN 0-85130-083-9.
• Pearcy, Arthur (1991). U.S. Coast Guard Aircraft Since 1916. Shrewsbury, UK: Airlife Publishing. ISBN 1-85310-118-4.
• Sapienza, Antonio Luis (June 2000). "Les premiers avions de transport commercial au Paraguay" [The First Commercial Transport Aircraft in Paraguay]. Avions: Toute l'Aéronautique et son histoire (in French) (87): 45–47. ISSN 1243-8650.
• "Stinson Restyles". Aviation Week & Space Technology. Vol. 36, no. 2. February 1937. pp. 35–36.
• Swanborough, F. G.; Bowers, Peter M. (1963). United States Military Aircraft since 1909. London: Putnam.
• Swanborough, Gordon; Bowers, Peter M. (1976). United States Navy Aircraft since 1911 (Second ed.). London: Putnam. ISBN 0-370-10054-9.
• Wegg, John (1990). General Dynamics Aircraft and their Predecessors. London: Putnam. ISBN 0-85177-833-X.

• Stinson SR-10F Reliant National Air and Space Museum, Smithsonian Institution
• Stinson UC-81 Reliant (Stinson AT-19/SR-10) Fleet Air Arm Archive^[usurped]
• Stinson SR-9 Alberta Aviation Museum
• (1944) T.O. No. 01-50KA-1 Pilot's Flight Operating Instructions for Army Model AT-19 Airplanes, British Model Reliant