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Kawanishi N1K1 Kyofu (Rex)

Imperial Japan (1943)
Picture of Kawanishi N1K1 Kyofu (Rex) Floatplane Fighter / Interceptor

The impressive Kawanishi N1K1 Kyofu fighting floatplane arrived to fulfill a wartime requirement that was no longer there.


Detailing the development and operational history of the Kawanishi N1K1 Kyofu (Rex) Floatplane Fighter / Interceptor.  Entry last updated on 5/22/2016. Authored by Staff Writer. Content ©www.MilitaryFactory.com

Early in World War 2 (1939-1945), Japanese authorities understood that their conquest of the Pacific would strain their carrier group's reach, limiting the effectiveness of fighters and bombers being launched from their decks. Expensive and complex airfield construction operations would also restrict forward-operating capability of the Empire and thus pressure fell to develop a system centered around use of floatplanes which did not require any fixed points on a map from which to operate from. The Empire of Japan became the only major player in the war to put an emphasis on dedicated "fighting floatplanes" (other powers simply relegated these types of aircraft for roles such as reconnaissance, gunnery spotting, and anti-ship warfare) as there was an understanding of their strategic limitations in the war going forwards.

Development on a dedicated fighting floatplane began in 1940 with the project hoping to capture an existing single-seat design with added floatplane capabilities that did not diminish fighter performance while retaining a suitable offensive punch. Kawanishi was eventually given the lead on the program while Nakajima was charged with developing a floatplane version of the famous Mitsubishi A6M "Zero" navy fighter to serve in the interim.

Kawanishi eventually returned with the N1K "Kyofu" which, unlike many floatplanes of the period, utilized a monoplane wing arrangement (as opposed to a biplane configuration). Its undercarriage showcased a large central float with smaller, retractable floats added under each wing. The fuselage was well-rounded and highly streamlined, tapering off at the empennage which fixed a single vertical tail fin and horizontal planes to either side. The single-seat cockpit was under a heavily framed canopy and offered generally decent vision about the aircraft - views naturally obstructed by the large main wing members and long nose. The engine was situated in the nose section and capped by two-bladed contra-propeller units, drive power coming from a Mitsubishi Kasei 14 radial engine of 1,460 horsepower output. Combat flaps were automatically adjustable in-flight based on the acceleration of the aircraft - a rather unique quality of this new aircraft. Armament was the same as on the A6M fighter, combining 2 x 20mm cannons with 2 x 7.7mm machine guns while a bomb load of up to 132 pounds (2 x 66 lb) could be held under the wings.
First flight of an N1K prototype was on May 6th, 1942 and testing unveiled generally poor results from the contra-propeller arrangement. As such, this feature was dropped in favor of a more conventional engine and gearbox driving a three-bladed propeller system. The move was also made to replace the engine from the Kasei 14 series radial to the Kasei 13 model of similar horsepower output. The retractable nature of the outboard, underwing floatplanes did not make it into the finalized form leaving these appendages fixed in place during flight. On the whole, however, IJN pilots evaluating the mount appreciated their new product - save for take-off characteristics which required additional attention at the controls. Once in the air, the fighting floatplane was a sound investment with excellent agility.

With the evaluation period over, the N1K was adopted as the N1K1 "Kyofu" and slated for introduction in 1943 as Japanese factories ramped up for the change. By this point in the war, the Japanese Navy was still betting their future on the success of its A6M Zero fighter to maintain air dominance in the theater and it appeared as if this was to be a reality until Allied tactics and warplanes caught up, and eventually surpassed, Japanese prowess in the skies. The changing face of war in 1943, coupled with a slow procurement scheme, meant that the N1K began arriving in useful numbers only after the Japanese had lost the initiative in the skies. As such, its intended role of forward-operating fighting floatplane was neutralized by the lack of forward-operating positions now having fallen to the Allied advance - essentially the N1K arrived to fulfill a battlefield role that was no longer there.

This led to production of N1K1 aircraft being ended rather quickly in March of 1944 with fewer than 100 having been delivered. While participating in some of the latter actions of the Pacific War, the series ended up as part of the homeland defense of Japan against mounting Allied bomber raids. At one point, the N1K1 was to see a successor with a larger engine built - this set to become the N1K2. However, only the designation was reserved and nothing came from this work. Earlier on, while development on the N1K floatplane was still ongoing, Kawanishi also managed to sell to Japanese authorities a version of its aircraft to serve as a land-based fighter - made faster and more streamlined by its lack of fixed float equipment. This became the N1K2-J "Shiden" ("George") fighter line which proved a worthy opponent to the vaunted American line-up of Grumman, Vought, and North American fighters in the Pacific skies. This aircraft went on to have a decidedly more impressive combat history despite being limited in available numbers.

The N1K1 was codenamed "Rex" by the Allies.






Our Data Modules allow for quick visual reference when comparing a single entry against contemporary designs. Areas covered include general ratings, speed assessments, and relative ranges based on distances between major cities.

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Relative Maximum Speed Rating
Hi: 400mph
Lo: 200mph
    This entry's maximum listed speed (304mph).

    Graph average of 300 miles-per-hour.
City-to-City Ranges
NYC
 
  LON
LON
 
  PAR
PAR
 
  BER
BER
 
  MOS
MOS
 
  TOK
TOK
 
  SYD
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  LAX
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  NYC
Graph showcases the Kawanishi N1K1 Kyofu (Rex)'s operational range (on internal fuel) when compared to distances between major cities.
Aviation Era
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Pie graph section
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Unit Production Comparison
Comm. Market HI*: 44,000 units
Military Market HI**: 36,183 units
89
89


  * Commercial Market High belongs to Cessna 172.

  ** Military Market High belongs to Ilyushin Il-2.


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Origin: Imperial Japan
Year: 1943
Type: Floatplane Fighter / Interceptor
Manufacturer(s): Kawanishi - Imperial Japan
Production: 89
Global Operators:
Imperial Japan
Historical Commitments / Honors:

Military lapel ribbon for Operation Allied Force
Military lapel ribbon for the Arab-Israeli War
Military lapel ribbon for the Battle of Britain
Military lapel ribbon for the Battle of Midway
Military lapel ribbon for the Berlin Airlift
Military lapel ribbon for the Chaco War
Military lapel ribbon for the Cold War
Military lapel ribbon for the Cuban Missile Crisis
Military lapel ribbon for the Falklands War
Military lapel ribbon for the French-Indochina War
Military lapel ribbon for the Golden Age of Flight
Military lapel ribbon for the 1991 Gulf War
Military lapel ribbon for the Indo-Pak Wars
Military lapel ribbon for the Iran-Iraq War
Military lapel ribbon for the Korean War
Military lapel ribbon for the 1982 Lebanon War
Military lapel ribbon for the Malayan Emergency
Military lapel ribbon for the attack on Pearl Harbor
Military lapel ribbon for the Six Day War
Military lapel ribbon for the Soviet-Afghan War
Military lapel ribbon for the Spanish Civil War
Military lapel ribbon for the Suez Crisis
Military lapel ribbon for the Vietnam War
Military lapel ribbon for Warsaw Pact of the Cold War-era
Military lapel ribbon for the WASP (WW2)
Military lapel ribbon for the World War 1
Military lapel ribbon for the World War 2
Military lapel ribbon for the Yom Kippur
* Ribbons not necessarily indicative of actual historical campaign ribbons. Ribbons are clickable to their respective campaigns/operations.
Measurements and Weights icon
Structural - Crew, Dimensions, and Weights:
Unless otherwise noted the presented statistics below pertain to the Kawanishi N1K1 Kyofu (Rex) model. Common measurements, and their respective conversions, are shown when possible.

Operational
CREW


Personnel
1


Dimension
LENGTH


Feet
34.78 ft


Meters
10.6 m


Dimension
WIDTH


Feet
39.37 ft


Meters
12 m


Dimension
HEIGHT


Feet
15.58 ft


Meters
4.75 m


Weight
EMPTY


Pounds
6,063 lb


Kilograms
2,750 kg


Weight
LOADED


Pounds
8,190 lb


Kilograms
3,715 kg

Engine icon
Installed Power - Standard Day Performance:
1 x Mitsubishi MK4C Kasei 13 radial piston engine developing 1,460 horsepower.

Performance
SPEED


Miles-per-Hour
304 mph


Kilometers-per-Hour
490 kph


Knots
265 kts


Performance
RANGE


Miles
652 mi


Kilometers
1,050 km


Nautical Miles
567 nm


Performance
CEILING


Feet
34,777 ft


Meters
10,600 m


Miles
6.59 mi


Performance
CLIMB RATE


Feet-per-Minute
2,980 ft/min


Meters-per-Minute
908 m/min

Supported Weapon Systems:

Graphical image of an aircraft medium machine gun
Graphical image of an aircrat automatic cannon
Graphical image of an aircraft conventional drop bomb munition
Armament - Hardpoints (2):

STANDARD:
2 x 20mm Type 99-1 cannons in wings
2 x 7.7mm Type 97 machine guns in engine cowling

OPTIONAL:
2 x 66 lb conventional drop bombs held underwing.
Variants: Series Model Variants
• N1K "Kyofu" - Base Series Name
• N1K1 - Initial production model of 1943; 89 examples completed.
• N1K2 - Proposed variant with larger engine; not produced.