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Kawanishi H8K (Emily)

Imperial Japan (1942)

Detailing the development and operational history of the Kawanishi H8K (Emily) Reconnaissance / Bomber Flying Boat Aircraft.

 Entry last updated on 5/22/2016; Authored by Staff Writer; Content ©

  Kawanishi H8K (Emily)  
Picture of Kawanishi H8K (Emily) Reconnaissance / Bomber Flying Boat Aircraft

The Kawanishi H8K Emily was arguably the best flying boat of the Second World War - considered by many to be on par with even the excellent British Short Sunderland.

The Empire of Japan seemed to be producing its best aircraft designs of the war towards the end of the conflict. The Kawanishi H8K (codenamed "Emily" by the Allies) was such an example. Bred to take the reigns of the similar but wholly outclassed Kawanishi H6K already in service, the H8K was developed to a new 1938 specification. The resulting design proved to be one of the more feared and respected Japanese weapons in the Pacific. If one would consider the type to be nothing more than a lumbering flying boat, you would overlook the impressive cannon armament, outstanding range, good performance capabilities and offensive firepower long enough to see that even American submarines were at the mercy of the "Emily".

The shortcomings of the H6K type were highly known by now, so much so that the Kawanishi company set about to right the wrongs with the addition of the H6K5 to the production line. Unfortunately, the ship of the H6K had already sailed and the H8K was designed to a new need. The H8K was characterized but its stout fuselage and single vertical tail fin. The cockpit sat high just forward of the shoulder-mounted wing assembly housing 4 x Mitsubishi brand engines of 1,850 horsepower (H8K2). As a land-based operator the H8K could call upon smallish wheels while under wing pontoons served it well on water. Initially, the H8K was found to be a poor performer in the latter role but service trials eventually ironed out the defects and the legend of the H8K was made.

Flying boats are not a weapon that one thinks of when considering the best offensive options available in a war but the H8K changed that thinking. Defensive armament was initially 4 x 7.7mm machine guns and 2 x 20mm cannons. Later developments would give rise to a 4 x 7.7mm and 5 x 20mm cannon-armed derivative in the H8K2 model. Add to this the improved armor protection, impressive speed and range and the ability to deliver torpedoes or bombs and you have a recipe for a true winner. The H8K was particularly effective in the anti-submarine role when married to an ASW radar, finding and sinking several American submarines during the course of its combat life.

The H8K, like the H6K before it, also appeared in dedicated transport roles either for VIp staff or combat ready troops. In the troop carrying role, the H8K could support up to 64 soldiers. These types are characterized with the "L" in their designation. Only four of the aircraft survive to war's end.
Any available statistics for the Kawanishi H8K (Emily) Reconnaissance / Bomber Flying Boat Aircraft are showcased in the areas immediately below. Categories include basic specifications covering country-of-origin, operational status, manufacture(s) and total quantitative production. Other qualities showcased are related to structural values (namely dimensions), installed power and standard day performance figures, installed or proposed armament and mission equipment (if any), global users (from A-to-Z) and series model variants (if any).
Kawanishi H8K2 (Emily) Specifications
National Flag Graphic
Imperial Japan
Year: 1942
Type: Reconnaissance / Bomber Flying Boat Aircraft
Manufacturer(s): Kawanishi - Imperial Japan
Production: 167
Supported Mission Types
Ground Attack
Close-Air Support
Airborne Early Warning
Electronic Warfare
Aerial Tanker
Passenger Industry
VIP Travel
Business Travel
Special Forces
Crew: 10
Length: 92.29 ft (28.13 m)
Width: 124.67 ft (38.00 m)
Height: 30.02 ft (9.15 m)
Empty Weight: 40,521 lb (18,380 kg)
MTOW: 71,650 lb (32,500 kg)

Installed Power
4 x Mitsubishi Kasei 22 14-cylinder air-cooled radial engines developing 1,850 horsepower each.

Standard Day Performance
Maximum Speed: 290 mph (467 kph; 252 kts)
Maximum Range: 4,461 mi (7,180 km; 3,877 nm)
Service Ceiling: 28,740 ft (8,760 m; 5.44 mi)
Rate-of-Climb: 1,624 ft/min (495 m/min)

1 x 20mm cannon in bow position
1 x 20mm cannon in dorsal position
1 x 20mm cannon in left blister position
1 x 20mm cannon in right blister position
1 x 7.7mm machine gun in beam position
1 x 7.7mm machine gun in beam position
1 x 7.7mm machine gun in beam position
1 x 7.7mm machien gun in beam position

Up to 4,409 lb (2,000 kg) of external stores OR 2 x 1,764 (800 kg) torpedoes

Operators List
Imperial Japan

Series Model Variants
• H8K1 - Prototype
• H8K1 (Navy Flying Boat Type 2, Model 11) - 14 produced; initial service models.
• H8K1-L - Dedicated Transport Variant
• H8K2 (Model 12) - Improved engine output through Mitsubishi Kasei 22 radials of 1,850 horsepower and defensive armament; ASW radar equipped; 120 produced.
• H8K2-L "Seiku" (Model 32) - Dedicated Transport Variant based on the H8K1 model.
• H6K3 - Two prototype experimental models based on the H8K2; featuring retractable wingtip floats and dorsal turret; blisters removed in favor of sliding gun hatches.
• H8K4 (Model 23) - Two conversion models fitted with different powerplants.

Supported Weapon Systems
Graphical image of an aircraft medium machine gun
Graphical image of an aircrat automatic cannon
Graphical image of an aircraft aerial torpedo