Kawanishi H8K

Kawanishi H8K
Type:	Flying boat
Design country:	Japan
Manufacturer:	Kawanishi Kōkūki
First flight:	December 31, 1940
Commissioning:	1942
Number of pieces:	167

The Kawanishi H8K (allied code name Emily ) was the most modern and most powerful long-range reconnaissance flying boat that was available to Japan during World War II . It was the world's most powerful aircraft of this type in World War II.

development

The aircraft was developed at the instigation of Rear Admiral Yamamoto Isoroku . In contrast to other Japanese seaplanes, this type outperformed all British and American aircraft (for example Sunderland and Coronado ) mainly due to its considerable power reserves and high payload capacity (the take-off mass was twice the empty mass). However, its use suffered from the severe shortage of qualified naval pilots, as it could only be flown by excellent pilots due to its size and its high wing loading of 200 kg / m² .

A series of 167 machines was built; the construction was based on the British short empire model. The aircraft was a cantilevered shoulder- wing monoplane with a normal tail unit in all-metal construction. It had a hull boat and rigid support floats with one step each. The H8K was driven by four motors Mitsubishi Kasei 12 (per 1805 PS ) or Kasei 22 (per 1825 hp). The fuel supply of up to 12,650 kg carried for long-distance flights was located in the fuselage and wings in self-sealing tanks .

As a result of the increasing American air superiority, the armament was constantly strengthened. It consisted in 1944 of five 20-mm automatic cannon and four to six machine guns (Bugstand, back stand, two swallows and tail turret). The extremely strong defensive armament earned the machine great respect from Allied pilots, wherever it was used in the Pacific region.

The H8K was able to carry 2000 kg of drop ammunition as an external load under the wings .

Versions

The later museum machine H8K2 (serial number 426) on NAS Norfolk during the 1970s

H8K1 : Name for the first three prototypes and the first 14 series machines, all with MK4A engines; later series machines had MK4B motors with the same power
H8K1-L : new name for the first prototype after the conversion to a transporter with more powerful MK4Q engines
H8K2 : the most important production model with MK4Q engines, reinforced armament, fully protected fuel tanks and ASV radar ; 112 of this type under the designation piece were Navy Type 2 flying boat model 12 produced
H8K2-L : series transporter derived from the H8K1-L for 29 to 64 passengers and reduced armament; as a marine type 2 transporter flying boat Seiku (clear sky) model 32 36 times built in series
H8K3 : Designation for two prototypes with retractable wing tip support floats and retractable machine gun stand on the back, not in series
H8K4 : new name for the H8K3 prototypes after the installation of Mitsubishi MK4T-B-Kasei-25b engines (1361 kW, 1825 PS), not built in series

Technical specifications

Three-sided view of the H8K3

Parameter	Kawanishi H8K2 (marine type 2 flying boat model 12)
Manufacturer	Kawanishi Kōkūki
Years of construction	1941-1945
crew	9
length	28.20 m
span	37.80 m
height	9.14 m
Wing area	161 m²
Empty mass	15,440 kg
Takeoff mass	normal 30,870 kg maximum 32,000 kg
drive	four Mitsubishi Kasei 12 , each 1,805 PS (1,328 kW) or four Kasei 22 , each 1,825 PS (1,342 kW)
Top speed	472 km / h at 5000 m altitude
Marching speed	300 km / h at 5000 m altitude
Rate of climb	300 m / min
Radius of action	2200 km
Flight duration	16 h at 300 km / h
Service ceiling	normal 6800 m maximum 8500 m
Range	normal 4800 km maximum 7000 km

Start of a Kawanishi H8K
The only surviving H8K in the Kanoya Museum in Japan
Rear stand of an H8K2

War effort

The Kawanishi H8K was used in patrol, reconnaissance, bombing and transport missions throughout the Pacific War.

The first combat mission took place on the night of March 4, 1942 in Operation K , the second air raid on Pearl Harbor . With the target out of range of the Marshall Islands flying boats , this bold attack involved submarine refueling at the French Frigate Shoals atoll , approximately 900 km northwest of Hawaii. Instead of using five machines to attack as planned, only two reached their target. Because of the clouds and the arranged darkening, it was difficult for them to orientate themselves and to find destinations. The two aircraft bombed Pearl Harbor with four 250 kg bombs each, but caused no significant damage and some wounded due to poor visibility. After dropping their bombs, they returned to the submarines, where they refueled and then flew back to the Marshall Islands. It was the longest flight route at this point in the war.

Assessment of the machine

The US aircraft historian René Francillon rates the Kawanishi H8K as "the most outstanding water-based fighter aircraft of the Second World War".

literature

William Green, Gordon Swanborough (Eds.): The unrivaled Emily - Best of the wartime big 'boats . In: AIR International April 1983, pp. 179-187

Web links

Commons : Kawanishi H8K - collection of images, videos and audio files

Individual evidence

↑ Edwin P. Hoyt: Yamamoto. The man who planned Pearl Harbor . McGraw-Hill, New York et al. a. 1990, p. 87.
↑ Steve Horn: The Second Attack on Pearl Harbor: Operation K and Other Japanese Attempts to Bomb America in World War II. US Naval Institute Press, 2005, ISBN 978-1-59114-388-8 .
^ René J. Francillon: Japanese Aircraft of the Pacific War . London: Putnam & Company, 1970 (2nd edition 1979). ISBN 978-0-370-30251-5 , p. 312

[1] Edwin P. Hoyt: Yamamoto. The man who planned Pearl Harbor . McGraw-Hill, New York et al. a. 1990, p. 87.

[2] Steve Horn: The Second Attack on Pearl Harbor: Operation K and Other Japanese Attempts to Bomb America in World War II. US Naval Institute Press, 2005, ISBN 978-1-59114-388-8 .

[3] René J. Francillon: Japanese Aircraft of the Pacific War . London: Putnam & Company, 1970 (2nd edition 1979). ISBN 978-0-370-30251-5 , p. 312