Kawasaki Ki-61 Hein (Tony)
The Ki-61's designers, Takeo Doi and Shin Owada, had worked under the German Richard Vogt, In December 1940 they were instructed to go ahead with the Ki-61, and one year later the prototype was flown, powered by an inverted V-12 inline engine, the Kawasaki Ha-40 being in effect a Daimler- Benz DB 601A built under licence.
The first production Ki-61-I fighters were deployed operationally in April 1943 when the 68th and 78th Sentais arrived in New Guinea. Named Hien (Swallow) in service (and codenamed 'Tony' by the Allies), the new aircraft proved popular with its pilots. Being well-armed and armoured, the type was a match for opposing American fighters. Its armament (of four 12.7-mm machine-guns) proved inadequate to knock down enemy bombers, and the Ki-61 I-hei(c) was introduced with a pair of 20-mm cannon in the nose, these being replaced in a small number of Ki-61 I-tei(d) fighters by two 30-mm cannon.
The Ki-61-I and Ki-61-I KAI remained in production until 1945, but in 1944 they were joined in service by the Ki- 61-II with more powerful Kawasaki Ha- 140 engine (producing 1119-kW); with a top speed of 610km/h this would have been an excellent fighter but for constant engine problems; yet when fully serviceable the Ki-61-II was one of the few Japanese fighters fully able to combat the Boeing B-29 at its normal operating altitude, particularly when armed with four 20-mm cannon. Excluding prototypes and development aircraft, production totalled 1,380 Ki-61-Is, 1,274 Ki- 61-I KAIs and 374 Ki-61-Ils.
Ki61I-ko(a) 2X7.7mm 2X12.7mm
Ki61I-hei(c) 2X12.7mm (nose) 2X20mm (MG151/20 imported by submarine from Germany)
Ki61I-tei(d) 2X20mm Ho-5 nose guns 2X12.7mm wing guns (also called Ki61I-kai, this had a longer fuselage and additional fuselage tank).
Engine: 1 x Kawasaki Ha-140, 1125kW
Max take-off weight: 3780-3825 kg / 8334 - 8433 lb
Empty weight: 2840 kg / 6261 lb
Wingspan: 12 m / 39 ft 4 in
Length: 9.16 m / 30 ft 1 in
Height: 3.7 m / 12 ft 2 in
Wing area: 20 sq.m / 215.28 sq ft
Max. speed: 610 km/h / 379 mph
Cruise speed: 400 km/h / 249 mph
Ceiling: 11000 m / 36100 ft
Range w/max.fuel: 1600 km / 994 miles
Range w/max.payload: 1100 km / 684 miles
Armament: 2 x 20mm cannons, 2 x 12.7mm machine-guns, 2 x 250kg bombs
Max speed: 423 mph @ 28,000 ft
Initial climb: 3,425 fpm
Time to 20,000 ft: 6.6 minutes
Max range: 2,120 miles