Warplanes of Japan: Mitsubishi J2M Raiden

Mitsubishi J2M Raiden

(IJAAF Photo)

Mitsubishi J2M3 Model 21 Raiden Navy Interceptor Fighter.

The Mitsubishi J2M Raiden (雷電, "Lightning Bolt") is a single-engined land-based fighteraircraft used by the Imperial Japanese Navy Air Service in the Second WorldWar. The Allied reporting name was "Jack". The J2M was designed by Jiro Horikoshi, creator of the Mitsubishi A6M Zero, tomeet 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 reliedon speed, climb performance, and armament at the expense of manoeuvrability.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 tothe propeller with an extension shaft.

Teething development problems stemming from the engine cooling system, and themain undercarriage members led to a slowdown in production. A continual set of modifications resulted in new variants being introduced with the ultimatehigh-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 (mountedin the side of the fuselage just behind the engine) that allowed the ratedpower 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 tobe terminated after only two experimental J2M4s were built.

The first few produced J2M2s were delivered to the development units inDecember 1942 but severe problems were encountered with the engines. Trials andimprovements took almost a year and the first batch of the serial built J2M2Model 11 was delivered to 381st Kōkūtai in December 1943. Parallel with theJ2M2, production of the J2M3 Raiden Model 21 started. The first J2M3s appearedin October 1943 but deliveries to combat units started at the beginning ofFebruary 1944.

The Raiden made its combat debut in June 1944 during the Battle of thePhilippine Sea. Several J2Ms operated from Guam and Saipan and a small numberof aircraft were deployed to the Philippines. Later, some J2Ms were based inJapanese airfields in Korea under Genzan Ku: Genzan (Wonsan); Ranan (Nanam);Funei (Nuren); Rashin (Najin); and Konan, for defense of these areas andfighting against Soviet Naval Aviation units.

Primarily designed to defend against the Boeing B-29 Superfortress heavybomber, the type was handicapped at high altitude by the lack of aturbocharger. However, its four-cannon armament supplied effective firepowerand 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 whenfour Raidens, accompanied by eight Mitsubishi A6M Zeros, all belonging to the302nd Kokutai, intercepted a formation of US Navy Grumman F6F Hellcats from theaircraft-carrier USS Yorktown during the morning of 15 August 1945 over theKanto Plain. In the engagement, that took place only two hours before Japanofficially announced its surrender, four Hellcats were lost along with twoRaidens 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 17,400ft (5,300 m),[3] and the J2M3 ("Jack 21") achieved a speed of 417 mph(671 km/h) at 16,600 ft (5,100 m).

Variants
J2M1 Prototype: fitted with the 1,044 kW (1,400 hp) Mitsubishi MK4C Kasei 1314-cylinder air-cooled radial engine, and armed with two 7.7 mm (.303 in) Type97 machine guns in the upper fuselage and two wing-mounted 20 mm Type 99 ModelII cannon. - Eight built.
J2M2 Model 11: Powered by 1,379 kW (1,850 hp) Mitsubishi MK4R-A Kasei 23a14-cylinder radial engine, same armament as the J2M1.
J2M3 Model 21: Armed with two wing-mounted 20 mm Type 99 Model II cannon andtwo 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-CKasei 23c engine. Many armament configurations have been reported, e.g.,fuselage-mounted oblique-firing 20 mm Type 99 Model I cannon designed to fireupward as it passed underneath a bomber, two wing-mounted 20 mm Type 99 ModelII cannon, and two wing-mounted 20 mm Type 99 Model I cannon. Problems withturbocharger; only two experimental versions were built.
J2M5 Model 33: High altitude variant powered by 1,357 kW (1,820 hp) MitsubishiMK4U-A Kasei 26a engine with mechanically driven supercharger, giving increasedhigh-altitude speed at the expense of range. Two 20 mm Type 99 cannon infuselage, 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 200rounds per gun.
J2M6 Model 31: Chronologically earlier than J2M4 and J2M5 this version wasbased on J2M3. Had wider cockpit and improved bubble canopy later used in J2M3built since July 1943.
J2M6a Model 31A: Chronologically earlier than J2M4 and J2M5 this version was basedon J2M3a.
Had wider cockpit and improved bubble canopy later used in J2M3a built sinceJuly 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.

After the decisive Battle of Midway in 1942 Japan's military leaders rushed tore-equip their forces for defense of the home islands. In fighter designs theinterceptor role now took priority over forward projection of offensive power.Allied forces, meanwhile, sought to establish air superiority overJapanese-held territories via B-29 bombing raids on industrial targets.

The struggle to meet production demands sparked a Japanese initiative torecruit shonenko (child labour) from Taiwan (Formosa). Though the target of25,000 youths was never reached, over 8,400 Taiwanese youths aged 12 to 14relocated to Mitsubishi plants to help build the J2M Raiden. The Allied advancetook its toll. In 1945 aircraft production in Japan collapsed. (Wikipedia)

(IJAAF Photos)

Mitsubishi J2M3 Model 21 Raiden Navy Interceptor Fighter, codenamed Jack, IJAAF.

Mitsubishi J2M3 Model 21 Raiden Navy Interceptor Fighter, codenamed Jack, in the factory where it was found, guarded by US troops. (USAAF Photo)

Mitsubishi J2M3 Model 21 Raiden Navy Interceptor Fighter, codenamed Jack, in USN markings. (USN Photo)

(USAAF Photos)

Mitsubishi J2M3 Model 21 Raiden Navy Interceptor Fighter, (Serial No. 3008), captured on the emergency airstrip at Dewey Boulevard, Manila in the Philippines. It was designated TAIC-SWPA S12, and test flown at Clark Field, Manila. This aircraft is shown in natural metal finish with pre-war rudder stripes. The engine of this aircraft seized on its second flight, ending its test evaluation.

The Mitsubishi J2M Raiden (“Thunderbolt”) was a single-engined land-based fighter aircraft used by the Imperial Japanese Navy Air Service. The Allied reporting name was “Jack”. A surviving J2M is on display in the Planes of Fame museum in Chino, California. Two captured J2Ms were U.S. Technical Air Intelligence Command (TAIC) tested using 92 octane fuel plus methanol, with the J2M2 achieving a speed of 655 km/h (407 mph) at 5,520 m (17,400 ft), and the J2M3 achieving a speed of 671 km/h (417 mph) at 4,980 m (16,600 ft). Four Raidens were shipped to the USA, with J2M5, USAAF FE-318 and FE-319 scrapped at Middletown in 1946, J2M3, FE-320 scrapped at Park Ridge ca. 1950 and FE-321 scrapped at Middletown in 1946.