The Stearman Model 6 Cloudboy was a 1930s
American training biplane designed and built by the
Stearman Aircraft Company
Stearman Aircraft Corporation was an aircraft manufacturer in Wichita, Kansas. Although the company designed a range of other aircraft, it is most known for producing the Model 75, which is commonly known simply as the "Stearman" or "Boein ...
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
The United States Army Air Corps (USAAC) was the aerial warfare service component of the United States Army between 1926 and 1941. After World War I, as early aviation became an increasingly important part of modern warfare, a philosophical ri ...
. 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 6A Cloudboy
:Initial civil production with a
Wright J-6 Whirlwind 5
The Wright R-540 Whirlwind was a series of five-cylinder air-cooled radial aircraft engines built by the Wright Aeronautical division of Curtiss-Wright. These engines had a displacement of 540 in³ (8.85 L) and power ratings of arou ...
engine, three built.
;Model 6C Cloudboy
:Re-engined with a
Wright J-6-9 Whirlwind (R-975-1), also designated YBT-3.
;Model 6D Cloudboy
:Re-engined with a
Pratt & Whitney Wasp Junior
The Pratt & Whitney R-985 Wasp Junior is a series of nine-cylinder, air-cooled, radial aircraft engines built by the Pratt & Whitney Aircraft Company from the 1930s to the 1950s. These engines have a displacement of ; initial versions produced ...
, also designated YBT-5
;Model 6F Cloudboy
:Re-engined with a
Continental A70 engine, also designated YBT-9A.
;Model 6H Cloudboy
:Re-engined with a
Kinner YR-720A
The Kinner C-5 was an American five cylinder radial engine for small general and sport aircraft of the 1930s.
Design and development
The C-5 was a development of the earlier R-5 with greater power and dimensions. The main change was the increa ...
engine, also designated YBT-9C.
;Model 6L Cloudboy
:Re-engined with a
Lycoming R-680-3
The Lycoming R-680 is a nine-cylinder air-cooled radial engine, the first aero engine produced by Lycoming. The engine was produced in two types, the E and B series; both are essentially the same. The B4E was available in a trainer version wi ...
engine, also designated YBT-9B

;Model 6P Cloudboy
:One 6F re-engined with 1
Wright J-5
The Wright R-790 Whirlwind was a series of nine-cylinder air-cooled radial aircraft engines built by Wright Aeronautical Corporation, with a total displacement of about and around . These engines were the earliest members of the Wright Whirlwin ...
engine
;YPT-9
:Military production variant of the Model 6A with a
Wright J-6 Whirlwind 5
The Wright R-540 Whirlwind was a series of five-cylinder air-cooled radial aircraft engines built by the Wright Aeronautical division of Curtiss-Wright. These engines had a displacement of 540 in³ (8.85 L) and power ratings of arou ...
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
Continental A70 (YR-545-1) engine, later converted to YPT-9B.
;YPT-9B
:One YPT-9 and one YPT-9A re-engined with a
Lycoming R-680-3
The Lycoming R-680 is a nine-cylinder air-cooled radial engine, the first aero engine produced by Lycoming. The engine was produced in two types, the E and B series; both are essentially the same. The B4E was available in a trainer version wi ...
engine.
;YPT-9C
:YBT-3 re-engined with a
Kinner YR-720A
The Kinner C-5 was an American five cylinder radial engine for small general and sport aircraft of the 1930s.
Design and development
The C-5 was a development of the earlier R-5 with greater power and dimensions. The main change was the increa ...
engine.
;YBT-3
:One YPT-9 re-engined with a
Wright J-6-9 Whirlwind, later converted to a YPT-9C.
;YBT-5
:One YPT-9 re-engined with a
Pratt & Whitney R-985-1 Wasp Junior
The Pratt & Whitney R-985 Wasp Junior is a series of nine-cylinder, air-cooled, radial aircraft engines built by the Pratt & Whitney Aircraft Company from the 1930s to the 1950s. These engines have a displacement of ; initial versions produced , ...
engine.
;XPT-943
:A primary trainer derived from the 6A for evaluation at
Wright Field
Wilbur Wright Field was a military installation and an airfield used as a World War I pilot, mechanic, and armorer training facility and, under different designations, conducted United States Army Air Corps and Air Forces flight testing. Lo ...
. 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 Army Air Corps
The United States Army Air Corps (USAAC) was the aerial warfare service component of the United States Army between 1926 and 1941. After World War I, as early aviation became an increasingly important part of modern warfare, a philosophical ri ...
Surviving aircraft
* 6002 – 6L airworthy at the
Candler Field Museum in
Williamson, Georgia
Williamson is a city in Pike County, Georgia, United States. The population was 352 at the 2010 census.
History
The community was named after Isaac Henry Williamson, an early settler.
The Georgia General Assembly incorporated Williamson as a tow ...
.
* 6003 – 6L airworthy at the
Western Antique Aeroplane & Automobile Museum
The Western Antique Aeroplane and Automobile Museum (WAAAM) is located in Hood River, Oregon, United States, adjacent to the Ken Jernstedt Memorial Airport. WAAAM is a nonprofit 501(c)(3) organization committed to the preservation of, and educati ...
in
Hood River, Oregon
The city of Hood River is the seat of Hood River County, Oregon, United States. It is a port on the Columbia River, and is named for the nearby Hood River. As of the 2020 census, the city population was 8,313. It is the only city in Oregon whe ...
. It was previously owned by the Golden Wings Flying Museum.
* 6004 – YPT-9B on display at the
Yanks Air Museum
The Yanks Air Museum is a non-profit 501 (c)(3) organization and museum dedicated to exhibiting, preserving and restoring American aircraft and artifacts in order to show the evolution of American aviation, located at Chino Airport in Chino, Cal ...
in
Chino, California
Chino ( ; Spanish for "Curly") is a city in the western end of San Bernardino County, California, United States, with Los Angeles County to its west and Orange County to its south in the Southern California region. Chino is adjacent to Chin ...
. 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
Lakeland is the most populous city in Polk County, Florida, part of the Tampa Bay Area, located along Interstate 4 east of Tampa. According to the 2020 U.S. Census Bureau release, the city had a population of 112,641. Lakeland is a principal c ...
.
Specifications (YPT-9B)
See also
Notes
References
*
*
*
*
External links
Aerofiles - StearmanAerofiles - Cloudboy 6A photoSan Diego Air & Space Museum Archives - Cloudboy 6C photo
{{Wright Field project numbers
Cloudboy
Cloudboy was an electronic music group from Dunedin, New Zealand, that recorded and performed between 1995 and 2003. Their music is described as dark and introspective, mixed with occasionally upbeat songs. The band had three main members, Dema ...
1930s United States military trainer aircraft
Biplanes
Single-engined tractor aircraft
Aircraft first flown in 1931