The Mitsubishi Kasei(火星,Mars?) was a two-row, 14-cylinder air-cooled radial engine built by Mitsubishi Heavy Industries and used in a variety of World War IIJapaneseaircraft, such as Mitsubishi J2M and Mitsubishi G4M. The Mitsubishi model designation for this engine was A10 while it was an experimental project, in service it was known as the MK4, and known as the Ha-101 & Ha-111 by the Army and Kasei by the Navy. According to unified designation code it was Ha-32 of the variants from 11 to 27.
Although originally ordered by the Imperial Japanese Navy, the Kasei was based on the earlier Mitsubishi Shinten engine, itself based originally on the Mitsubishi Kinsei. Produced in a wide variety of models, the Kasei began with a rated power of 1,530 horsepower (1,140 kW), with a gradual evolution to 1,850 horsepower (1,380 kW) in later wartime versions. Three variants were developed for the Japanese Navy starting in 1939. It was also later adopted by the Imperial Japanese Army as the Ha-101 engine. Unified code was Ha-32.
Physically, the engine had a rather large 1,322 millimetres (52.0 in) diameter compared to the 1,180 millimetres (46.5 in) of the Nakajima Homare engine. Its size and weight meant it was a challenging engine to use on single engine fighters.
1,530 horsepower (1,140 kW), 2450 rpm at takeoff
1,410 horsepower (1,050 kW), 2350 rpm at 1,000 metres (3,300 ft)
1,380 horsepower (1,030 kW), 2350 rpm at 4,000 metres (13,000 ft)
MK4B [Ha-32] 12 - same as MK4A 11
MK4C [Ha-32] 13 - with extended propeller shaft
1,460 horsepower (1,090 kW), 2450 rpm at takeoff
1,420 horsepower (1,060 kW), 2350 rpm at 2,600 metres (8,500 ft)
1,300 horsepower (970 kW), 2350 rpm at 6,000 metres (20,000 ft)
MK4D [Ha-32] 14 - with contra-rotating shafts
MK4E [Ha-32] 15 - with improved altitude performance
MK4P [Ha-32] 21
1,850 horsepower (1,380 kW), 2600 rpm at takeoff
1,680 horsepower (1,250 kW), 2500 rpm at 2,600 metres (8,500 ft)
1,540 horsepower (1,150 kW), 2500 rpm at 6,000 metres (20,000 ft)
MK4Q [Ha-32] 22 - same as MK4A 21
MK4R [Ha-32] 23 - Water-injection
1,820 horsepower (1,360 kW), 2600 rpm at takeoff
1,600 horsepower (1,200 kW), 2500 rpm at 1,300 metres (4,300 ft)
1,520 horsepower (1,130 kW), 2500 rpm at 4,100 metres (13,500 ft)
MK4R-C [Ha-32] 23c - 1,820 horsepower (1,360 kW) - Fitted with a turbo charger that allowed an output of 1,420 horsepower (1,060 kW) to be maintained up to 30,000 feet (9,144 m) instead of only 15,750 feet (4,801 m)
MK4S [Ha-32] 24 - Same power as the MK4P 21 with contra-rotating shafts