AP 118 · No. 10 Section II · Aircraft Plate 147 / 336

Plate 147 of 336 · Second World War · Long-range patrol flying boat

Kawanishi H8K2 Type 2 Flying Boat

H8K2 c/n 426 ‘T-31’, painted as Kawanishi H8K2 Type 2 Flying Boat Model 12, manufacturer’s number 426, ‘T-31’ of the Imperial Japanese Navy’s 801st Kokutai, the only H8K to survive, as displayed at the JMSDF Kanoya Air Base Museum in Kagoshima: a large four-engined patrol flying boat with four Mitsubishi Kasei 22 radials in long nacelles on a high, tapered wing spanning 38 m, a deep, narrow two-step hull with a glazed bow turret, a stepped cockpit, a dorsal turret and beam blisters, fixed strut-braced wingtip floats, a tall single fin and a 20 mm cannon in the tail, shown level on its beaching gear: IJN dark green upper surfaces and hull sides down to the chine, a light grey planing bottom, light grey undersides to the wings, tailplane and floats, red hinomaru outlined in white on the hull and plain on the wings, yellow leading edges on the inner wings, a yellow ‘T-31’ and a small yellow emblem on the fin, white draft marks along the hull, and red-brown propellers with red spinners (no H8K is in a UK museum; shape from H8K three-views scaled to the published dimensions and checked against photographs of this aircraft at Kanoya and Tokyo; window and hatch positions, the wing-root fillet and the float struts are approximated, and the two dark bands across the fin are painted as photographed).

3D model

Turn it over

A procedural model built in Blender from published dimensions, drawings and photographs, painted as Kawanishi H8K2 Type 2 Flying Boat Model 12, manufacturer’s number 426, ‘T-31’ of the Imperial Japanese Navy’s 801st Kokutai, the only H8K to survive, as displayed at the JMSDF Kanoya Air Base Museum in Kagoshima: a large four-engined patrol flying boat with four Mitsubishi Kasei 22 radials in long nacelles on a high, tapered wing spanning 38 m, a deep, narrow two-step hull with a glazed bow turret, a stepped cockpit, a dorsal turret and beam blisters, fixed strut-braced wingtip floats, a tall single fin and a 20 mm cannon in the tail, shown level on its beaching gear: IJN dark green upper surfaces and hull sides down to the chine, a light grey planing bottom, light grey undersides to the wings, tailplane and floats, red hinomaru outlined in white on the hull and plain on the wings, yellow leading edges on the inner wings, a yellow ‘T-31’ and a small yellow emblem on the fin, white draft marks along the hull, and red-brown propellers with red spinners (no H8K is in a UK museum; shape from H8K three-views scaled to the published dimensions and checked against photographs of this aircraft at Kanoya and Tokyo; window and hatch positions, the wing-root fillet and the float struts are approximated, and the two dark bands across the fin are painted as photographed). Drag to orbit, scroll or pinch to zoom · download .glb (2.0 MB)

Data plate

Specification

First flight, number built and top speed are for the whole family (H8K2 (Allied name ‘Emily’)); engine, crew and dimensions are for the H8K2 c/n 426 ‘T-31’ modelled here.

History

The H8K

In 1938 the Imperial Japanese Navy asked Kawanishi for a four-engined flying boat to replace its H6K, with more speed, range and armament than the American and British boats of the day. Shizuo Kikuhara’s team drew a large, clean high-wing monoplane with a deep, narrow hull to cut drag, fixed wingtip floats and Mitsubishi Kasei radials. The first prototype flew in January 1941. On the water it was a handful, throwing up heavy spray and porpoising on take-off, and Kawanishi deepened the hull and added spray strips before it was accepted as the Navy Type 2 Flying Boat.

The H8K went into action almost at once. In March 1942 two H8K1s flew from Wotje in the Marshall Islands to bomb Pearl Harbor, refuelling from submarines at French Frigate Shoals on the way; cloud covered Oahu and their bombs did no damage. The main production version, the H8K2, had more powerful Kasei 22 engines, and later aircraft carried search radar. It was fast for a flying boat, could patrol for more than a day, and was armed with 20 mm cannon in the bow, dorsal and tail turrets and in the beam blisters, with 7.7 mm guns in hatches. It had armour and protected fuel tanks too, and Allied fighter pilots found it a hard aircraft to shoot down; the Allies called it ‘Emily’.

H8Ks flew long reconnaissance patrols, bombing raids and transport flights across the Pacific and Indian Oceans until 1945, and a transport version, the H8K2-L Seiku, carried up to 64 passengers. Kawanishi built 167 H8Ks of all versions. Many experts rank it the best flying boat of the Second World War. One survives, in Japan; none is in a UK museum.

This airframe

H8K2 c/n 426 ‘T-31’

426The airframe modelled

Manufacturer’s number 426 is the only H8K left in the world. It served with the 801st Kokutai as ‘T-31’ and was found at Takuma, on Shikoku, by the Americans at the end of the war. It was shipped to the United States for evaluation by the US Navy and photographed at Norfolk, Virginia, in 1949, and was then kept in storage for three decades. In 1979 it was returned to Japan and displayed at the Museum of Maritime Science in Tokyo, and in 2004 it moved to the Japan Maritime Self-Defense Force’s Kanoya Air Base Museum in Kagoshima, where it stands outside on its beaching gear. The model shows it as it is displayed there: dark green upper surfaces and hull sides down to the chine over a light grey planing bottom and light grey undersides, red hinomaru outlined in white on the hull and plain on the wings, yellow leading edges on the inner wings, a yellow ‘T-31’ and a small emblem on the fin, white draft marks along the hull, and red-brown propellers with red spinners. Its shape comes from H8K three-views scaled to the published dimensions and checked against photographs of this aircraft. The positions of some windows and hatches, the curved fillets where the wing meets the hull, and the float struts are approximated, and two dark bands across the fin, whose meaning is uncertain, are painted as they appear in photographs.

Where to see one

Not on charge

The only survivor was returned to Japan from the United States in 1979 and is displayed at the Kanoya Air Base museum.

All 336 plates

Profiles and models are procedural interpretations built in Blender from published dimensions, three-view drawings and photographs of each airframe. Treat the museum aircraft as the reference.