Mitsubishi Ki-1

The Mitsubishi Ki-1 was a bomber aircraft built by Mitsubishi for the Imperial Japanese Army in the 1930s. The Ki-1 was based on the militarized Junkers S36, the K37. The K37 prototype was brought to Japan and tested in combat in the Manchurian Incident of 1931, following which the Imperial Japanese Army Air Force authorized Mitsubishi to produce both heavy and light bomber variations. . The Mitsubishi Ki-1 flew for the first time in 1933. Already obsolete by the time of its introduction, the Ki-1 was used in pacification of Manchukuo and in north China during the early stages of the Second Sino-Japanese War, in areas where danger from enemy fighter planes was minimal. A total of 219 aircraft were built in two versions between March 1933 and April 1936.

Mitsubishi Ki-1
Class Aircraft
Type Bomber
Manufacturer Mitsubishi Aircraft Corporation
Origin Japan
Country Name Origin Year
Japan 1931
Country Name Operational Year Retirement Year
Japan 1933 1940 View
ManufacturerName Production From Production To Quantity
Mitsubishi Aircraft Corporation 219 View

The Mitsubishi Ki-1 was a low-wing, cantilever monoplane with fixed landing gear, twin fins and rudders, and was powered by two 701 kW (940 hp) Ha-2-2 water-cooled radial engines, giving a maximum speed of 220 km/h (140 mph). The pilot and co-pilot were seated in tandem under an enclosed canopy, while gunners sat in semi-enclosed nose and dorsal gun turrets, each armed with a single 7.7 mm (.303 in) machine gun. The usable bomb load was up to 1,500 kg (3,310 lb).

The Ki-1 shared a similar configuration with the Junkers S36 first flown in 1927. Militarized into the Junkers K37 by Junker's Swedish subsidiary AB Flygindustri at Limhamn near Malmö, it was able to reach altitudes not reachable for the fighters of 1927. However, as soon as 1930 this advantage was lost due to British developments such as the Bristol Bulldog fighter, and Junkers was not successful in selling the design. In 1931 however representatives of Mitsubishi Nainenki K. K. from Japan visited the Limhamn facilities to study some of the military conversions of Junkers aircraft. The sole K37 prototype S-AABP (ex D-1252 S36-prototype), as well as all development papers were purchased in part by funds raised by donations in Japan. The aircraft got the name Aikoku No.1 (patriotic gift). In any case, the wing design of the Ki-2 was essentially the same as that of the Junkers, with some modifications, but the Ki-1 itself shared nothing whatsoever with the German design other than a similar appearance.

The K37 prototype was brought to Japan and tested in combat during the Manchurian Incident of 1931, following which the Imperial Japanese Army Air Force authorized Mitsubishi to produce both heavy and light bomber variations. The heavy bomber version, Ki-1, was much larger than the original Junkers K37 and first flew in August 1932. A total of 118 aircraft were built in two versions between March 1933 and April 1936.

The Mitsubishi Ki-1 was initially designated Army Type 93-1 Heavy Bomber under the former aircraft nomenclature system used by the Japanese military. Already obsolete by the time of its introduction, it found use during the counterinsurgency operations of the Pacification of Manchukuo, and as well as limited use during the Second Sino-Japanese War.

The design was upgraded to the Mitsubishi Ki-1-II (Army Type 93-2 Heavy Bomber) with a strengthened airframe and slightly more powerful 723 kW (970 hp) Ha-2-3 radial engines, which increased maximum speed to 230 km/h (140 mph). However, even with the new engines, the Ki-1 was still underpowered, and was unable to maintain altitude during single engine flights, which proved to be a serious issue during the aircraft's operational service due to lack of reliability of the engines. It was replaced in 1937 by the Fiat BR.20.

General characteristics

  • Crew: 4
  • Length: 14.8 m ( ft in)
  • Wingspan: 26.50 m (86 ft 11.25 in)
  • Height: 4.92 m ( ft in)
  • Wing area: 90.74 m ( ft)
  • Empty weight: 4880 kg ( lb)
  • Gross weight: 8100 kg (17857 lb)
  • Powerplant: 2 x Ha-2-2 radial, 701 kW (940 hp)eacheach

Performance

  • Maximum speed: 220 km/h (137 mph)
  • Service ceiling: 5000 m ( ft)

Armament

  • 3 x 7.7-mm (0.303-in) machine-guns
  • 1500 kg (3307 lb) of bombs

End notes