Mitsubishi Ki-1 “Army Type 93” Heavy Bomber, c. 1935.

Mitsubishi Ki-1 “Army Type 93” Heavy Bomber, c. 1935, in formation over the Great Wall of China.

The Mitsubishi Ki-1, also known as Mitsubishi Army Type 93 Heavy Bomber, was a bomber built by Mitsubishi for the Imperial Japanese Army in the 1930s. The Ki-1 design was heavily based on the Junkers K 37 and the prototype flew in the early 1930s.

Already obsolete by the time of its introduction in 1932, it did find use during the counterinsurgency operations of the Pacification of Manchukuo, as well as limited use during the Second Sino-Japanese War.

The Ki-1 shared a similar configuration with the Junkers S 36 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, Junkers was not successful in selling the design.

In 1931, representatives of Mitsubishi from Japan visited the Limhamn facilities to study some of the military conversions of Junkers aircraft. The sole K37 prototype was purchased in part by funds raised by public donation in Japan, and it was given the name Aikoku ichi-ban [“Patriotic gift #1”].

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 Ki-1 variant, when it first flew in August 1932, was much larger than the original Junkers K37 prototype. A total of 118 Ki-1 aircraft were built in two versions between March 1933 and April 1936.

The design was upgraded to the Mitsubishi Ki-1-II with a strengthened airframe and slightly more powerful engines. But, the Ki-1 remained underpowered and was replaced in 1937 by imports of the Italian Fiat BR.20.

: Mitsubishi Ki-1 “Army Type 93” heavy bomber, c. 1935.

: Mitsubishi Ki-1 “Army Type 93” heavy bomber, c. 1935.

Performance

Crew: 4
Maximum speed: 220 km/h (140 mph, 120 kn)
Service ceiling: 5,000 m (16,000 ft)