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Ki-100
General characteristics
Crew: 1
Length: 8.82 m (28 ft 11 in)
Wingspan: 10.48 m (34 ft 4 in)
Height: 3.75 m (12 ft 4 in)
Wing area: 20 m² (215 ft²)
Empty weight: 2,525 kg (5,567 lb)
Loaded weight: 3,495 kg (7,705 lb)
Powerplant: 1× Mitsubishi Ha 112-II radial engine, 1,119 kW (1,500 hp) at 6,000 m (19,685 ft)
Performance
Maximum speed: 580 km/h (360 mph)
Range: 2,200 km (1,367 mi)
Service ceiling: 36,090 feet (11,000 m)
Rate of climb: 16.8 m/s (3,300 ft/min)
Wing loading: kg/m² (lb/ft²)
Power/mass: kW/kg (hp/lb)
Maximum dive speed: 850 km/h (528 mph)
Armament
2x 20 mm wing-mounted Ho-5 cannons, 250 20x94 mm rounds/gun
2x 12.7 mm fuselage-mounted Ho-103 machine guns, 250 12.7x81 mm rounds/gun
Ki-61
General characteristics
Crew: One
Length: 8.94 m (29 ft 4 in)
Wingspan: 12.00 m (39 ft 4 in)
Height: 3.70 m (12 ft 2 in)
Wing area: 20.00 m² (215.28 ft²)
Airfoil: NACA 2R 16 wing root, NACA 24009 tip
Internal fuel capacity: 550 L (145.2 US gal)
External fuel capacity: 2x 200 L (53.8 US gal) drop tanks
Empty weight: 2,630 kg (5,800 lb)
Loaded weight: 3,470 kg (7,650 lb)
Powerplant: 1× Kawasaki Ha-40 liquid-cooled inverted V-12, 875 kW (1,175 hp)
Performance
Maximum speed: 580 km/h (360 mph) at 5,000 m (16,405 ft)
Range: 580 km (360 mi)
Service ceiling: 11,600 m (38,100 ft)
Rate of climb: 15.2 m/s (2,983 ft/min)
Wing loading: 173.5 kg/m² (35.5 lb/ft²)
Power/mass: 0.25 kW/kg (0.15 hp/lb)
Time to altitude: 7.0 min to 5,000 m (16,405 ft)
Armament
2x 20 mm Ho-5 cannon, 120 rounds/gun
2x 12.7 mm (0.50 in) Ho-103 machine guns, 200 rounds/gun
Same speed between the two, Ki-100 has a greater rate of climb and longer range; but the Ki-61 has a slightly higher ceiling, and its lighter, so probably turns better.