The Rikugun Ki-93 was a prototype
Japan
Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...
ese twin-engined
fighter aircraft
Fighter aircraft are fixed-wing military aircraft designed primarily for air-to-air combat. In military conflict, the role of fighter aircraft is to establish air superiority of the battlespace. Domination of the airspace above a battlefield ...
of the
Second World War. Designed by the Army Aerotechnical Research Institute, to be a
heavy fighter armed with large calibre
cannon to serve in the
anti-shipping or
bomber destroyer roles, only one example of the Ki-93 was completed; this was damaged on its maiden flight, and destroyed by American bombing before it could be flown again.
Development and design
In mid 1941, a team was set up at the Japanese Army Aerotechnical Research Institute (or ''Rikugun Kokugijutsu Kenkyujo'', known by the abbreviation Giken) to study advanced military aircraft. The team drew up preliminary designs for a twin-engined heavy fighter for the
Imperial Japanese Army Air Service, to be powered by two Mitsubishi Ha-211 radial engines and estimated to reach a speed of 680 km/h (422 mph). In July 1942, the design, along with some of the team from Giken, was passed to the First Army Air Arsenal (''Dai-Ichi Rikugun Kokusho'' or ''Kosho'') at
Tachikawa for further development. Here, the design was refined, with more powerful
Mitsubishi Ha-214
The is a group of autonomous Japanese multinational companies in a variety of industries.
Founded by Yatarō Iwasaki in 1870, the Mitsubishi Group historically descended from the Mitsubishi zaibatsu, a unified company which existed from 1870 t ...
radials substituted and a heavy cannon armament added.
['' Air International'' May 1977, p.252.]
Approval to build prototypes of the new fighter, designated Ki-93, was given on 22 February 1943.
['' Air International'' May 1977, p.254.] The Ki-93 was a low-winged
monoplane of all metal construction, with the crew of two sitting in tandem under a canopy at the front of the fuselage, and a ventral gondola slung under the fuselage to accommodate large
cannons. The wing was of
laminar flow
In fluid dynamics, laminar flow is characterized by fluid particles following smooth paths in layers, with each layer moving smoothly past the adjacent layers with little or no mixing. At low velocities, the fluid tends to flow without lateral mi ...
section.
Two variants were planned, the Ki-93-Ia bomber destroyer, armed with a 57 mm and two 20 mm cannon, and the Ki-93-Ib anti-shipping aircraft, which would have a 75 mm gun in the gondola and would also carry two 250 kg (550 lb) bombs.
[Francillon 1970, p.244.]
The first prototype proved to be overweight, while the new engines gave much less power than expected, delivering only 1,970 hp compared with the expected 2,400 hp. The Ki-93 made its first flight on 8 April 1945 from
Tachikawa airfield; a successful 20 minute test of its low-speed handling characteristics, piloted by Lt. Moriya of the ''Koku Shinsa-bu'' (Air Examination Department) with 2nd Lt. Ikebayashi in the second seat. Unfortunately, the pilot undershot the runway and touched down in soft soil, ground-looping the aircraft and tearing off the port
undercarriage
Undercarriage is the part of a moving vehicle that is underneath the main body of the vehicle. The term originally applied to this part of a horse-drawn carriage, and usage has since broadened to include:
*The landing gear of an aircraft.
*The ch ...
leg and engine mount, also bending the six-blade
propeller
A propeller (colloquially often called a screw if on a ship or an airscrew if on an aircraft) is a device with a rotating hub and radiating blades that are set at a pitch to form a helical spiral which, when rotated, exerts linear thrust upon ...
. Repairs were completed in four weeks but, the night before the scheduled second test flight, a
B-29
The Boeing B-29 Superfortress is an American four-engined propeller-driven heavy bomber, designed by Boeing and flown primarily by the United States during World War II and the Korean War. Named in allusion to its predecessor, the B-17 Fly ...
bombing raid on Tachikawa destroyed the hangar housing the aircraft.
["A Japanese rara avis...The Giken Fighter", ''AIR International'', Bromley, Kent, UK, May 1977, Volume 12, Number 5, pages 254-255 .]
Specifications (performance estimated, Ki-93-Ia armament)
See also
Notes
References
* Francillon, René J. ''Japanese Aircraft of the Pacific War''. London: Putnam & Company, 1970. .
*"The Giken Fighter". ''
Air International
''AIR International'' is a British aviation magazine covering current defence aerospace and civil aviation topics. It has been in publication since 1971 and is currently published by Key Publishing Ltd.
History and profile
The magazine was fir ...
'', May 1977, Vol 12 No. 5. pp. 251–255.
External links
www.warbirdsresourcegroup.org
{{Japanese Army Aircraft Designation System
1940s Japanese fighter aircraft
Low-wing aircraft
Aircraft first flown in 1945
Twin piston-engined tractor aircraft