Ranger V-770

V-770
	Preserved Ranger V-770

The Ranger V-770 was an American air-cooled inverted V-12 aero-engine developed by the Ranger Aircraft Engine Division of the Fairchild Engine & Aircraft Corporation in the early 1930s.^[2]

Design and development[]

In 1931, the V-770 design was put to paper, based on the Ranger 6-440 series of inverted inline air-cooled engines, and test flown in the Vought XSO2U-1 Scout. In 1938 it was tested in the Curtiss SO3C Seamew and found to be unreliable with a tendency to overheat in low-speed flight.^[3]^[4] By 1941 a more developed V-770 was installed in the Fairchild XAT-14 Gunner prototype and found satisfactory for the production Fairchild AT-21 Gunner gunnery school aircraft.^[5]

Produced from 1941 to 1945, the V-770 featured a two-piece aluminum alloy crankcase, steel barreled cylinders with integral aluminum alloy fins and aluminum alloy heads. The V-770 was the only American inverted V12-type inline air-cooled engine to reach production. The engine was used in a relatively small number of Army Air Forces aircraft, among them the Fairchild AT-21 twin-engine trainer of which approximately 175 were built,^[1] and in the two Bell XP-77s.

Variants[]

V-770-4: Installed in the Vought XSO2U-1 Scout
V-770-6: Installed in the XAT-14 Gunner prototype, intended for the Ryan SOR-1 Scout
V-770-7: Installed in the Bell XP-77 light-weight fighter prototype
V-770-8: Installed in the Curtiss SO3C Seamew Scout.^[4]
V-770-9: Installed in the XAT-6E Texan prototype.^[5]
V-770-11: Installed in the Fairchild AT-21 Gunner.^[5]
V-770-15: Installed in the Fairchild AT-21 Gunner.^[5]
SGV-770C-1: Tested in the Curtiss XF6C-7 Hawk Fighter-Bomber at 350 hp.^[4]
SGV-770D-5: Developed for post-war commercial use,^[2] 700 hp (kW) at 3,600 RPM, weight 870 lb (395 kg), height 31.11 in (790 mm), length 74.92 in (1,900 mm), width 33.28 in (846 mm)

Applications[]

Specifications (SGV-770C-1)[]

Data from Janes Fighting Aircraft of World War II (1989) ^[2]

General characteristics

Type: 12-cylinder inverted Vee piston engine
Bore: 4 in (101.6 mm)
Stroke: 5 ¹⁄₈ in (130.2 mm)
Displacement: 773 in³ (12.6 L)
Length: 62 in (1,574.8 mm)
Width: 28 in (711.2 mm)
Height: 32.2 in (817.88 mm)
Dry weight: 730 lb (331 kg)

Components

Valvetrain: Two overhead camshafts, one per cylinder bank, gear driven
Supercharger: Single-Speed, Single-Stage, produced 45 inches of mercury (1.5 bar, 7.5 psi) at take-off
Fuel system: Holley non-icing carburetor
Fuel type: 87 octane petrol
Oil system: Full pressure type
Cooling system: Air-cooled

Performance

Power output: 520 hp at 3,150 rpm (387.7 kW)
Specific power: 0.673 hp/in³
Compression ratio: 6.5:1
Power-to-weight ratio: 0.71 hp/lb

Survivors[]

Carolinas Aviation Museum 1 restored engine in storage
Myers Aviation, Inc. Oshkosh, WI 2 engines in storage

References[]

Wikimedia Commons has media related to Ranger V-770.

↑ ^1.0 ^1.1 "Ranger V-770 Inverted". National Museum of the USAF. http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=853. Retrieved 2008-11-07. Includes photo
↑ ^2.0 ^2.1 ^2.2 Jane, Frederick Thomas; Bridgman, Leonard; Gunston, Bill (1989). 0-517-67964-7 "Jane's Fighting Aircraft of World War II". London: Random House. ISBN 1-85170-493-0. http://books.google.co.uk/books?q=editions:ISBN 0-517-67964-7.
↑ Smith, Herschel H. (1986). "Aircraft Piston Engines: From the Manly Balzer to the Continental Tiara". Sunflower University Press. ISBN 978-0-89745-079-9. http://books.google.com/?id=w1XIAAAACAAJ. ^{[dead link]}
↑ ^4.0 ^4.1 ^4.2 Eden, Paul; Moeng, Soph (2002). "The Complete Encyclopedia of World Aircraft". London: Amber Books. ISBN 978-0-7607-3432-2. http://books.google.com/?id=6xMYAAAACAAJ.
↑ ^5.0 ^5.1 ^5.2 ^5.3 Swanborough, F. G.; Bowers, Peter M. (1964). "United States Military Aircraft Since 1909". New York: Putnam. ISBN 0-85177-816-X. http://books.google.com/?id=3QZUAAAAMAAJ&q=V-770.

All or a portion of this article consists of text from Wikipedia, and is therefore Creative Commons Licensed under GFDL.
The original article can be found at Ranger V-770 and the edit history here.

[Museum-1] 1.0 ^1.1 "Ranger V-770 Inverted". National Museum of the USAF. http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=853. Retrieved 2008-11-07. Includes photo

[Janes-2] 2.0 ^2.1 ^2.2 Jane, Frederick Thomas; Bridgman, Leonard; Gunston, Bill (1989). 0-517-67964-7 "Jane's Fighting Aircraft of World War II". London: Random House. ISBN 1-85170-493-0. http://books.google.co.uk/books?q=editions:ISBN 0-517-67964-7.

[3] Smith, Herschel H. (1986). "Aircraft Piston Engines: From the Manly Balzer to the Continental Tiara". Sunflower University Press. ISBN 978-0-89745-079-9. http://books.google.com/?id=w1XIAAAACAAJ. ^{[dead link]}

[EdenMoeng-4] 4.0 ^4.1 ^4.2 Eden, Paul; Moeng, Soph (2002). "The Complete Encyclopedia of World Aircraft". London: Amber Books. ISBN 978-0-7607-3432-2. http://books.google.com/?id=6xMYAAAACAAJ.

[Swanborough-5] 5.0 ^5.1 ^5.2 ^5.3 Swanborough, F. G.; Bowers, Peter M. (1964). "United States Military Aircraft Since 1909". New York: Putnam. ISBN 0-85177-816-X. http://books.google.com/?id=3QZUAAAAMAAJ&q=V-770.

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