The Aichi H9A served as a flying boat for the Imperial Japanese Navy Air Service, utilised primarily for crew training in the early years of World War II.
This rare model remained undetected by Allied forces until the spring of 1945 and consequently, it was never given an Allied reporting name.
The H9A, a twin-engine parasol-wing flying boat, was designated as the AM-21 design by Aichi.
It was developed in response to the Imperial Japanese Navy’s requirement for an advanced seaplane trainer for the future crew members of the four-engine Kawanishi H8K “Emily” flying boat.
The design work commenced in January 1940, and the first of three prototypes took flight in September 1940.
The aircraft typically had a crew of five, with additional seating for three trainee crew members.
Between May and June 1942, the Aichi H9A served in various secondary roles, such as anti-submarine missions along the Japanese coastlines, transportation, paratrooper training, and liaison duties.
Specifications
Crew
5
Capacity
3 Students
Length
16.95 m (55 ft 7 in)
Wingspan
24 m (78 ft 9 in)
Height
5.25 m (17 ft 3 in)
Wing area
63.3 m2 (681 sq ft)
Empty weight
4,900 kg (10,803 lb)
Gross weight
7,000 kg (15,432 lb)
Max take-off weight
7,500 kg (16,535 lb)
Powerplant
2 × Nakajima Ha-1 Kotobuki 42
Or
2 x 43 9-cyinder air-cooled radial piston engine,
530 kW (710 hp) each for take-off
455 kW (610 hp) at 3,000 m (9,843 ft)
Propellers
3 bladed propellers
Performance
Maximum speed
317 km/h (197 mph, 171 kn) at 3,000 m (9,843 ft)
Cruise speed
222 km/h (138 mph, 120 kn) at 1,000 m (3,281 ft)
Range
2,148 km (1,335 mi, 1,160 nmi)
Service ceiling
6,780 m (22,240 ft)
Rate of climb
4.5 m/s (890 ft/min)
Time to altitude
3,000 m (9,843 ft) in 11 minutes, 14 seconds
Wing loading
110.6 kg/m2 (22.7 lb/sq ft)
Power/mass
0.151 kW/kg (0.092 hp/lb)
Armament
Guns
1× flexible 7.7 mm (.303 in) Type 92 machine gun in bow and dorsal hatches
Bombs
2 × 250 kg (551 lb) bombs or depth charges.
Sources Japanese Aircraft 1910–1941-R C Mikesh & A Shorzoe. The Xplanes of Imperial Japanese Army & Navy 1924-1945-Illustrated Warplane History.
