Stearman Cloudboy

Model 6 Cloudboy
The YBT-3
Role	Training biplane
Manufacturer	Stearman Aircraft Company
First flight	1931
Primary user	United States Army Air Corps
Produced	1930-1931
Number built	7

The Stearman Model 6 Cloudboy was a 1930s American training biplane designed and built by the Stearman Aircraft Company of Wichita, Kansas.

History

The Cloudboy was designed as a commercial or military trainer. Due to economic pressure during the Great Depression, only a few aircraft were built. Three civil models were built, followed by four similar aircraft for evaluation by the United States Army Air Corps. Designated YPT-9 by the Army, it failed to gain any orders. All models went through a number of engine changes (resulting in new designations for both the military and civil aircraft).

Variants

Model 6L Stearman Cloudboy (YBT-9B), N787H

Model 6A Cloudboy

Initial civil production with a 165 hp (123 kW) Wright J-6 Whirlwind 5 engine, three built.

Model 6C Cloudboy

Re-engined with a 300 hp (220 kW) Wright J-6-9 Whirlwind (R-975-1), also designated YBT-3.

Model 6D Cloudboy

Re-engined with a 300 hp (220 kW) Pratt & Whitney Wasp Junior, also designated YBT-5

Model 6F Cloudboy

Re-engined with a 165 hp (123 kW) Continental A70 engine, also designated YBT-9A.

Model 6H Cloudboy

Re-engined with a 170 hp (130 kW) Kinner YR-720A engine, also designated YBT-9C.

Model 6L Cloudboy

Re-engined with a 200 hp (150 kW) Lycoming R-680-3 engine, also designated YBT-9B

YBT-5

Model 6P Cloudboy

One 6F re-engined with 1 220 hp (160 kW) Wright J-5 engine

YPT-9

Military production variant of the Model 6A with a 165 hp (123 kW) Wright J-6 Whirlwind 5 engine, four built (one converted to YPT-9A, one to YPT-9B, one to YBT-3 and one YBT-5).

YPT-9A

One YPT-9 re-engined with a 165 hp (123 kW) Continental A70 (YR-545-1) engine, later converted to YPT-9B.

YPT-9B

One YPT-9 and one YPT-9A re-engined with a 200 hp (150 kW) Lycoming R-680-3 engine.

YPT-9C

YBT-3 re-engined with a 170 hp (130 kW) Kinner YR-720A engine.

YBT-3

One YPT-9 re-engined with a 300 hp (220 kW) Wright J-6-9 Whirlwind, later converted to a YPT-9C.

YBT-5

One YPT-9 re-engined with a 300 hp (220 kW) Pratt & Whitney R-985-1 Wasp Junior engine.

XPT-943

A primary trainer derived from the 6A for evaluation at Wright Field. Formed the origins of the Stearman NS and PT-13 for the US Navy and USAAC respectively.

X-70

Alternative company designation for the XPT-943.

Operators

United States

United States Army Air Corps

Surviving aircraft

• 6002 – 6L airworthy at the Candler Field Museum in Williamson, Georgia.
• 6003 – 6L airworthy at the Western Antique Aeroplane & Automobile Museum in Hood River, Oregon. It was previously owned by the Golden Wings Flying Museum.
• 6004 – YPT-9B on display at the Yanks Air Museum in Chino, California. It was previously owned by the Boeing School of Aeronautics and was acquired by the museum in 1987.
• 6010 – 6C airworthy with Robert Lock of Lakeland, Florida.

Specifications (YPT-9B)

Data from United States Military Aircraft since 1909

General characteristics

• Crew: 2

Performance

See also

Related lists

• List of military aircraft of the United States

References

• Andrade, John (1979). U.S.Military Aircraft Designations and Serials since 1909. Midland Counties Publications. ISBN 0-904597-22-9.
• Swanborough, F.G; Bowers, Peter M. (1963). United States Military Aircraft since 1909. London: Putnam.
• Taylor, Michael J. H. (1989). Jane's Encyclopedia of Aviation. London: Studio Editions.
• The Illustrated Encyclopedia of Aircraft (Part Work 1982-1985). Orbis Publishing. p. 2958. {{cite book}}: Cite has empty unknown parameter: |coauthors= (help)

External links

• Aerofiles - Stearman
• Aerofiles - Cloudboy 6A photo
• San Diego Air & Space Museum Archives - Cloudboy 6C photo