The Kreider-Reisner Challenger (later the Fairchild KR series) was an American utility biplane aircraft designed and produced by the

Kreider-Reisner Aircraft Company The Kreider-Reisner Aircraft Company was an American flying service and aircraft manufacturer from 1923 to 1929. History The Kreider-Reisner Aircraft Company was formed at Hagerstown, Maryland in 1923 as a sub-contractor. By September 1925 the c ...

, which was later taken over by the Fairchild Aircraft Company.

Development

The Challenger was related to the earlier

Waco 10 The Waco 10/GXE/Waco O series was a range of three-seat open-cockpit biplanes built by the Advance Aircraft Company, later the Waco Aircraft Company. Design and development The Waco 10 was a larger span development of the Waco 9, both single-engi ...

, later renamed as the Waco GXE. A poorly documented Kreider-Reisner aircraft, the C-1, was used to modify the Waco in stages to the Challenger. The Challenger was a conventional mixed-construction

biplane A biplane is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation. While ...

with a fixed tailskid landing gear. It had two open tandem cockpits for a pilot (at the rear), and passenger (forward) and was powered by a 90 hp (67 kW)

Curtiss OX-5 The Curtiss OX-5 was an early V-8 American liquid-cooled aircraft engine built by Curtiss. It was the first American-designed aircraft engine to enter mass production, although it was considered obsolete when it did so in 1917.Smith, 1981, pa ...

inline engine. A number of variants were built designated the C-3 Challenger and C-4 Challenger which had detailed differences and different engines fitted. Late in 1928 the company introduced a new and slightly smaller design designated the C-6 Challenger. In 1929 the company was bought by the Fairchild Aircraft Company who continued the production of the C-4 as the Fairchild KR-34 and the C-6 as the

Fairchild KR-21 The Kreider-Reisner KR-21-A was a 1928 American two-seat monoplane. It was designed and built by the Kreider-Reisner Aircraft Company of Hagerstown, Maryland. Fairchild Aircraft took over Kreider-Reisner in 1929 and continued to build them, as th ...

. Although not built by Fairchild the C-2 was redesignated the Fairchild KR-31. To act as an engine testbed a KR-21 was modified to use a Fairchild 6-390 engine (later named Ranger) and changes were made to the wing and landing gear geometry. The modified aircraft was known as the Fairchild KR-125. In 1931 a similar aircraft without the geometry changes but with a Ranger engine was sold under the designation KR-135. In 1930, the KR-34CA, a military version of the Fairchild KR-34 based on the Kreider-Reisner C-4C Challenger design, was built in

Farmingdale, New York Farmingdale is an incorporated Political subdivisions of New York#Village, village on Long Island within the Oyster Bay (town), New York, Town of Oyster Bay in Nassau County, New York, Nassau County, New York (state), New York. The population was ...

. A light attack craft, it had two .30 caliber Browning machine guns mounted on the nose, firing through the propellers. The Chinese version had bomb racks under the fuselage. Two of this military version of the Fairchild KR-34 were sold to the warlord generals

Liu Wenhui Liu Wenhui (; 1895 – 24 June 1976) was a Chinese general and warlord of Sichuan province (Sichuan clique). At the beginning of his career, he was aligned with the Kuomintang (KMT), commanding the Sichuan-Xikang Defence Force from 1927 to 1929. ...

and Liu Xiang in

Szechwan Sichuan (; zh, c=, labels=no, ; zh, p=Sìchuān; alternatively romanized as Szechuan or Szechwan; formerly also referred to as "West China" or "Western China" by Protestant missions) is a province in Southwest China occupying most of the ...

Province.

Variants

''Fairchild type numbers in brackets'' Kreider-Reisner C-4C Challenger SI

;C-2 Challenger (KR-31) :Initial production version,

V-8 engine ;C-3 Challenger :C-2 with detail changes and

Warner Scarab The Warner Scarab is an American seven-cylinder radial aircraft engine, that was manufactured by the Warner Aircraft Corporation of Detroit, Michigan in 1928 through to the early 1940s. In military service the engine was designated R-420. Vari ...

radial engine ;C-4 Challenger (KR-34) :C-2 with detail changes and

Comet 7-D The Comet 7-cylinder radials were a family of air-cooled radial engines, designed and built by the Comet Engine Corporation at Madison, Wisconsin from around 1927. Design and development Comet designed the 7-cylinder radial series to take advan ...

. ;C-6 Challenger (KR-21) :Smaller (6% span reduction) version of C-2 with

;KR-34CA :1930 attack aircraft version of the C-4C ;KR-125 :One KR-21 modified to an engine test bed for the

Fairchild 6-390 Fairchild may refer to: Organizations * Fairchild Aerial Surveys, operated in cooperation with a subsidiary of Fairey Aviation Company * Fairchild Camera and Instrument * List of Sherman Fairchild companies, "Fairchild" companies * Fairchild Fash ...

. ;KR-135 :Production version of KR-21 with inline engine. ;

Parks P-1 The Parks P-1 was an American three-seat sport biplane that was built in the late 1920s. Design and development Based in St.Louis, pilot, salesman and entrepreneur Oliver Parks founded an air school, airline and aircraft manufacturing business s ...

:Challenger C-2 with radiator between undercarriage legs. About 45 built. ;

Parks P-2 The Parks P-2, powered by a 150 hp Axelson-Floco B engine, was a biplane designed and built at the Parks Air College in the United States circa 1929. A change in engine type to the Wright J-6 The Wright Whirlwind was a family of air-cool ...

:Challenger with

Axelson (company) The Axelson Aircraft Engine Company was a manufacturer of aircraft engines based in Los Angeles Los Angeles ( ; es, Los Ángeles, link=no , ), often referred to by its initials L.A., is the List of municipalities in California, largest c ...

radial and split-axle undercarriage. Parks P-2A had

Wright J-6-5 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 around ...

radial. Less than 20 built. ;

Ryan Speedster The Parks P-2, powered by a 150 hp Axelson-Floco B engine, was a biplane designed and built at the Parks Air College in the United States circa 1929. A change in engine type to the Wright J-6 resulted in the Parks P-2A, which was ultimately ...

:later name for Parks P-2 and Parks 2A . ;

Hammond Sportster Hammond may refer to: People * Hammond Innes (1913–1998), English novelist * Hammond (surname) * Justice Hammond (disambiguation) Places Antarctica * Hammond Glacier, Antarctica Australia *Hammond, South Australia, a small settlement in South ...

:Parks P-2A with wide track undercarriage. Seven built.

Specifications (KR-34)

References

* * The Illustrated Encyclopedia of Aircraft (Part Work 1982-1985), 1985, Orbis Publishing, Page 1674 {{Fairchild aircraft 1920s United States civil utility aircraft KR-34

Challenger Challenger, Challengers, or The Challengers may refer to: Entertainment Comics and manga * Challenger (character), comic book character * ''Challengers'' (manga), manga by Hinako Takanaga Film and TV * ''The Challengers'' (TV series), a 1979 ...

Single-engined tractor aircraft Biplanes Aircraft first flown in 1928 Conventional landing gear