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| Mitsubishi J2M Raiden (“Lightning Bolt”). |
The
Mitsubishi J2M Raiden ("Lightning Bolt") is a single-engined
land-based fighter aircraft used by the Imperial Japanese Navy Air
Service in World War II. The Allied reporting name was "Jack".
This
is another design by vaunted designer Jiro Horikoshi, who was the
subject of Hayao Miyazaki’s controversial animated feature film “The
Wind Rises” (2013). Engine problems and coming along too late in the
conflict made it less successful than Horikoshi’s more famous design -
the A6M Zero.
The
J2M was designed by Jiro Horikoshi, creator of the Mitsubishi A6M Zero,
to meet the 14-Shi (14th year of the Showa reign, or 1939 in the
Western calendar) official specification. It was to be a strictly
local-defense interceptor, intended to counter the threat of
high-altitude bomber raids, and thus relied on speed, climb performance,
and armament at the expense of maneuverability. The J2M was a sleek,
but stubby craft with its oversized Mitsubishi Kasei engine buried
behind a long cowling, cooled by an intake fan and connected to the
propeller with an extension shaft.
Teething development problems
stemming from the engine cooling system, and the main undercarriage
members led to a slowdown in production. A continual set of
modifications resulted in new variants being introduced with the
ultimate high-altitude variant, the J2M4 Model 34 flying for the first
time in August 1944. It had a 1,420 hp Kasei 23c engine equipped with a
turbocharger (mounted in the side of the fuselage just behind the
engine) that allowed the rated power to be maintained up to 9,100 m
(29,900 ft). Two upward-aimed, oblique-firing (aimed at seventy degrees)
20 mm cannons, mounted in the German Schräge Musik style, were fitted
behind the cockpit with the four wing cannons retained. Unresolved
difficulties with the turbocharger caused the project to be terminated
after only two experimental J2M4s were built.
The
first few produced J2M2s were delivered to the development units in
December 1942 but severe problems were encountered with the engines.
Trials and improvements took almost a year and the first batch of the
serial built J2M2 Model 11 was delivered to 381st Kōkūtai in December
1943. Parallel with the J2M2, production of the J2M3 Raiden Model 21
started. The first J2M3s appeared in October 1943 but deliveries to
combat units started at the beginning of February 1944.
The
Raiden made its combat debut in June 1944 during the Battle of the
Philippine Sea. Several J2Ms operated from Guam and Saipan and a small
number of aircraft were deployed to the Philippines. Later, some J2Ms
were based in Japanese airfields in Korea under Genzan Ku: Genzan
(Wonsan); Ranan (Nanam); Funei (Nuren); Rashin (Najin); and Konan, for
defense of these areas and fighting against Soviet Naval Aviation units.
Primarily
designed to defend against the Boeing B-29 Superfortress heavy bomber,
the type was handicapped at high altitude by the lack of a turbocharger.
However, its four-cannon armament supplied effective firepower and the
use of dive and zoom tactics allowed it to score occasionally.
Insufficient numbers and the American switch to night bombing in March 1945 limited its effectiveness.
J2Ms
took part in one of the final aerial combats of the Second World War
when four Raidens, accompanied by eight Mitsubishi A6M Zeros, all
belonging to the 302nd Kokutai, intercepted a formation of US Navy
Grumman F6F Hellcats from the aircraft-carrier USS Yorktown during the
morning of 15 August 1945 over the Kanto Plain. In the engagement, that
took place only two hours before Japan officially announced its
surrender, four Hellcats were lost along with two Raidens and two Zeros.
U.S.
Technical Air Intelligence Command (TAIC) tested two captured J2Ms
using 92 octane fuel plus methanol and calculated maximum speeds using
measurements. The J2M2 ("Jack 11") achieved a speed of 407 mph (655
km/h) at 17,400 ft (5,300 m), and the J2M3 ("Jack 21") achieved a speed
of 417 mph (671 km/h) at 16,600 ft (5,100 m).
Type: Fighter aircraft
Manufacturer: Mitsubishi Heavy Industries
Primary user: Imperial Japanese Navy
Number built: 621
Introduction date: December 1942
First flight: 20 March 1942
Retired: August 1945
Specifications (J2M3)
Crew: 1
Length: 9.945 m (32 ft 8 in)
Wingspan: 10.8 m (35 ft 5 in)
Height: 3.81 m (12 ft 6 in)
Wing area: 20.05 m2 (215.8 sq ft)
Empty weight: 2,839 kg (6,259 lb)
Gross weight: 3,211 kg (7,079 lb)
Powerplant:
1 × Mitsubishi MK4R-A Kasei 23a 14-cylinder air-cooled radial piston engine, 1,300 kW (1,800 hp) for take-off
1,174 kW (1,575 hp) at 1,800 m (5,900 ft)
1,051 kW (1,410 hp) at 4,800 m (15,700 ft)
Propellers: 4-bladed constant-speed metal propeller
Maximum speed: 587 km/h (365 mph, 317 kn) at 5,300 m (17,400 ft)
Cruise speed: 351 km/h (218 mph, 190 kn)
Range: 1,898 km (1,179 mi, 1,025 nmi)
Service ceiling: 11,700 m (38,400 ft)
Time to altitude: 6,000 m (20,000 ft) in 6 minutes 14 seconds
Wing loading: 171.3 kg/m2 (35.1 lb/sq ft)
Power/mass: 0.391 kW/kg (0.238 hp/lb)
Armament:
2x 20 mm (0.787 in) Type 99 Mark 2 machine gun inboard wing-mounted with 190 rpg
2x Type 99 Mark 1 machine gun outboard wing-mounted with 210 rpg
2× 60 kg (132 lb) bombs
or
2 × 200 L (53 US gal; 44 imp gal) drop tanks or a larger central drop tank
Variants
J2M1 Prototype: fitted
with the 1,044 kW (1,400 hp) Mitsubishi MK4C Kasei 13 14-cylinder
air-cooled radial engine, and armed with two 7.7 mm (.303 in) Type 97
machine guns in the upper fuselage and two wing-mounted 20 mm Type 99
Model II cannon. Eight built.
J2M2 Model 11: Powered by 1,379 kW (1,850 hp) Mitsubishi MK4R-A Kasei 23a 14-cylinder radial engine, same armament as the J2M1.
J2M3 Model 21: Armed with two wing-mounted 20 mm Type 99 Model II cannon and two wing-mounted 20 mm Type 99 Model I cannon.
J2M3a Model 21A: Armed with four wing-mounted 20 mm Type 99 Model II cannon.
J2M4 Model 32: Prototype
fitted with the 1,357 kW (1,820 hp) Mitsubishi MK4R-C Kasei 23c engine.
Many armament configurations have been reported, e.g., fuselage-mounted
oblique-firing 20 mm Type 99 Model I cannon designed to fire upward as
it passed underneath a bomber, two wing-mounted 20 mm Type 99 Model II
cannon, and two wing-mounted 20 mm Type 99 Model I cannon. Problems with
turbocharger; only two experimental versions were built.
J2M5 Model 33: High
altitude variant powered by 1,357 kW (1,820 hp) Mitsubishi MK4U-A Kasei
26a engine with mechanically driven supercharger, giving increased
high-altitude speed at the expense of range. Two 20 mm Type 99 cannon in
fuselage, two 20 mm Type 99 Model II cannon in wings.
J2M5a Model 33A: Armed
with four wing-mounted 20 mm Type 99 Model II cannon. Wing cannon were
harmonized in trajectory and ballistics with each having 200 rounds per
gun.
J2M6 Model 31: Chronologically
earlier than J2M4 and J2M5 this version was based on J2M3. Had wider
cockpit and improved bubble canopy later used in J2M3 built since July
1943.
J2M6a Model 31A: Chronologically
earlier than J2M4 and J2M5 this version was based on J2M3a. Had wider
cockpit and improved bubble canopy later used in J2M3a built since July
1943. One J2M6a was built.
J2M7 Model 23A: J2M3 powered by Kasei 26a engine, a few built.
J2M7a Model 23A: J2M3a powered by Kasei 26a engine, a few built.
Production
After
the decisive Battle of Midway in 1942 Japan's military leaders rushed
to re-equip their forces for defense of the home islands. In fighter
designs the interceptor role now took priority over forward projection
of offensive power. Allied forces, meanwhile, sought to establish air
superiority over Japanese-held territories via B-29 bombing raids on
industrial targets.
The struggle to meet production demands
sparked a Japanese initiative to recruit shonenko (child labor) from
Taiwan (Formosa). Though the target of 25,000 youths was never reached,
over 8,400 Taiwanese youths aged 12 to 14 relocated to Mitsubishi plants
to help build the J2M Raiden.
The Allied advance took its toll. In 1945 aircraft production in Japan collapsed.
Allied
bombing raids of Nagoya began in December 1944 and progressively
disrupted production of the J2M. A direct hit on the Mitsubishi Dai San
Kokuki Seisakusho aircraft plant caused the complete loss of airframes,
machine tools, and jigs. This halted further production.
Production
generally suffered less from direct hits on factories, which were rare,
but from attacks on suppliers and consequent shortages of material and
construction tools.
Operators
Japan
Imperial Japanese Navy Air Service
Surviving Aircraft
J2M3
Model 21 c/n 3014 is on display at the Planes of Fame Air Museum in
Chino, California. It was brought from Japan in 1945 for technical
evaluation by the US Navy. Later declared surplus, it was displayed at
the Travel Town Museum in Griffith Park, Los Angeles before it was
acquired in 1958 by Planes of Fame founder Edward T. Maloney.
Bibliography
The Complete Encyclopedia of World Aircraft New York: Barnes & Noble, 1977.
Francillon,
René J. (1979). Japanese aircraft of the Pacific War. London: Putnam
(new edition 1987 by Putnam Aeronautical Books).
Green, William. Air Enthusiast Magazine, Quarterly Volume 1, Number 2 Bromley, Kent: Pilot Press, 1971.
Green,
William. Warplanes of the Second World War, Volume Three: Fighters.
London: Macdonald & Co. (Publishers) Ltd., 1973, First edition 1961.
Huggins,
Mark (January–February 2004). "Hunters over Tokyo: The JNAF's Air
Defence of Japan 1944–1945". Air Enthusiast (109): 66–71.
Izawa,
Yasuho & Holmes, Tony. J2M Raiden and N1K1/2 Shiden/Shiden-Kai
Aces. Osprey Publishing. 2016 Aircraft of the Aces Number 129.
Ledet,
Michel & Osuo, Katshuhiko (January 2001). "Mitsubishi J2M Raiden:
l'intercepteur de la Marine japonaise" [Mitsubishi J2M Raiden: The
Japanese Navy's Interceptor]. Avions: Toute l'Aéronautique et son
histoire (in French) (94): 8–16.
Ledet,
Michel & Osuo, Katshuhiko (February 2001). "Mitsubishi J2M Raiden:
l'intercepteur de la Marine japonaise". Avions: Toute l'Aéronautique et
son histoire (in French) (95): 20–28.
United
States Strategic Bombing Survey Aircraft Division. Mitsubishi Heavy
Industries, Ltd. Corporation Report I, Washington, D.C. 1947.
United
States Strategic Bombing Survey Aircraft Division. Army Air Arsenal and
Navy Air Depots Corporation Report XIX, Washington, D.C. 1947.
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December
1945: Japanese aircraft taken over by the Allies in British Malaya were
tested and evaluated by Japanese naval aviators under close supervision
of RAF officers from Seletar Airfield. Here two Mitsubishi J2M Raiden
fighters (known to the Allies as 'Jack'), belonging to the 381 Kokutai
of Imperial Japanese Navy Air Service, are flying in close formation
during their evaluation flight.
|
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| A J2M3 Model 21 in the Planes of Fame. |
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| Mitsubishi J2M. |
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April
21, 1945: Mitsubishi J2M-3 Raiden fighter ("Jack") in USAAC markings,
of the South West Pacific area technical air intelligence unit.
|
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| Surrender of Japan, August-September 1945. Japanese planes at a Tokyo Airfield, Japan. Photograph received September 21, 1945. |
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| Over
the Philippines, a formation of aircraft led by a captured Japanese
Navy interceptor fighter aircraft Mitsubishi J2M Raiden (Thunderbolt,
allied code name "Jack"), of the Technical Air Intelligence Unit, South
West Pacific Area (SWPA) located at Clark Field, Luzon (Philippines)
from the end of January 1945. The aircraft was recovered from a
makeshift airstrip in Manila when American forces recaptured the city.
Other aircraft in the formation are a Royal Navy Seafire (lower left)
and a U.S. Navy Grumman F6F-5 Hellcat. The Mitsubishi J2M's development
to full combat status was delayed by technical problems and production
indecision, resulting in employment being mainly in the defence of Japan
from USAAF bombing. |
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December
1945: Japanese aircraft taken over by the Allies in British Malaya
were tested and evaluated by Japanese naval pilots under the supervision
of Royal Air Force officers. Here a Mitsubishi J2M Raiden (known to the
Allies as a 'Jack'), belonging to the 381 Kokutai of Imperial Japanese
Navy Air Service, has its engine run prior to flight whilst Japanese
ground crew wait in attendance at RAF Seletar.
|
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December
1945: Japanese aircraft taken over by the Allies in Malaya were tested
and evaluated by Japanese naval pilots under the supervision of Royal
Air Force officers. Here Japanese ground crew watch one of their
aircraft. Behind them stands a Mitsubishi J2M Raiden (known to the
Allies as a 'Jack').
|
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| Over
the Philippines, a Japanese Navy interceptor fighter aircraft
Mitsubishi J2M Raiden (Thunderbolt, allied code name "Jack") in flight,
of the Technical Air Intelligence Unit, South West Pacific Area (SWPA)
located at Clark Field, Luzon (Philippines) from the end of January
1945. The aircraft was recovered from a makeshift airstrip in Manila
when American forces recaptured the city. The Mitsubishi J2M's
development to full combat status was delayed by technical problems and
production indecision, resulting in employment being mainly in the
defense of Japan from USAAF bombing. |
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| 1943: Prototype Mitsubishi J2M3 Raiden 21 from Yokosuka Naval Air Technical Arsenal testing unit. |
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| Third production J2M1. |
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| J2M3. |
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| J2M3a Raiden 21a, 302nd Air Corps, operating in the defense of Yokosuka. |
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| J2M3a, 302nd Air Corps, operating in the defense of Yokosuka. |
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| Three-view drawing of J2M3. Starboard side view at top is J2M4. |
