Nakajima AT2 / Ki-34 / L1N1
Nakajima acquired from Douglas Aircraft in the USA licence-construction rights for the DC-2 civil transport. In 1935 a smaller, twin-engine light transport based on the configuration of the DC-2 was designed by Nakajima under the designation AT-1. This was not built, but redesign resulted in an improved AT-2 with two 580-hp / 433kW Nakajima Kotobuki 2-1 radial engines, and this was flown in prototype form on 12 September 1936.
It was an all-metal low- wing cantilever monoplane with slim tapered wings and tailplane and retractable undercarriage. Power was provided by two Nakajima Kotobuki 2-1 radials. Test flights began on September 12, 1936, from Ojima airfield and proved successful, only minor adjustments and modifications being necessary.
The AT 2 was placed in production for civil use, fitted with later Kotobuki 41 radial engines each of 780 hp. Accommodation was provided for a crew of three and eight passengers in an enclosed cabin. A total of 32 AT 2s were delivered to Dai Nippon Koku K K (Greater Japan Airlines Company) and Manchurian Airlines for use on internal and external routes up to 1940.
In 1937 the Koku Hombu (Japanese army air headquarters) was anxious to introduce a modern transport aircraft into the air force inventory and turned to the AT 2, already established as an efficient aircraft. Designated Ki-34, deliveries began the same year and it immediately went into service as the Army Type 97 Transport.
After producing 19 of the aircraft, Nakajima turned over production to the Tachikawa company who built a further 299 up to 1942.
Some of this total were transferred by the army for navy use, and were redesignated Navy Type AT-2 Transport (Nakajima L1N1). Both civil and military versions were allocated the Allied codename 'Thora', and were in use throughout the Pacific war.
Ki-34 / L1N1
Engines: 2 x Nakajima "Kotobuki-41", 529kW
Max take-off weight: 5250 kg / 11574 lb
Empty weight: 3500 kg / 7716 lb
Wingspan: 19.92 m / 65 ft 4 in
Length: 15.3 m / 50 ft 2 in
Height: 4.15 m / 13 ft 7 in
Wing area: 49.2 sq.m / 529.58 sq ft
Max. speed: 360 km/h / 224 mph
Ceiling: 7000 m / 22950 ft
Range w/max.fuel: 1200 km / 746 miles
Nakajima Ki-34 / L1N1 THORA