FR006 Nakajima Ko-4

History:
The Nieuport NiD-29 C1 is a fighter designed by Gustave Delage in 1918. WWI ended before it was produced. In 1920 it was selected as new fighter by the French Aéronautique Militaire and the delivery to the units started in 1922. 700 of this aircraft were produced. They were also produced under license in Belgium, Japan, Italy and Siam. They were used by the air forces of other countries as Spain, Sweden, Argentina, Kwansi, China and Manchuria.

The Nieuport NiD-29 C1 was selected by the Japanese Army to replace the Spad XIII and Ni.24 which equipped the fighter units. In year 1923, one machine was bought in France. The NiD-29 was built under license by Nakajima firm which produced 608 machines. This type was called Ko-4 by Japanese. The Hiko Rentai (Air regiments) 1, 3, 4, 7 and 8 were equipped with Ko-4. Fighter units with Ko-4 took part in the invasion of Manchuria in 1931 and 1932. A lot of fighter schools were equipped with Ko-4 in 1937 (up to some sources, some were still in service in 1941).

In China, the Kwansi government bought in 1935 ten Nakajima Ko-4s for advanced training tasks. The following year the Kwansi joined the central Nanking government. All the aircraft were integrated into the China Air Force. At the end of 1937 seven Ko-4s were in service for training duties in the CAF.
 In Manchuria four Ko-4s were bought. After the japanese invasion, these aircraft were put into service by the Japanese Army. In 1937 one Ko-4 was used by the new Manchukuo military aviation.

In 1923 the Siam Aeronautical Service chose the Nieuport NiD-29 for its fighter units. Twelve machines were ordered to France as well as forty Hispano 8Fb engines. The construction under license was also negotiated. The NiD-29 C1 was named Bin Khpa Laï 4 (it means fighter model 4). Forty aircrafts were built by local factory. The 52 Bin Khpa Laï 4 equipped four fighter squadrons. In 1937 they were replaced by Curtiss Hawks II & III (up to some sources, several machines remained in service for training in 1941).

Specifications (NiD-29): single-engined biplane fighter. Engine: Hispano-Suiza 8Fb, V-8, liquid cooled, 300 CV. Wingspan: 9,70 m, lenght 6,50 m, hight 2,50m. Maximum speed : 213 km/h at 4 000 m, operational ceiling 7 700 m. Range: 580 km. Weaponry: 2 machine-guns.