Genzan Air Group

The Genzan Air Group, also known in Japanese as Genzan Kaigun Kōkūtai, was an Imperial Japanese Navy Air Service aircraft and airbase garrison unit active from November 1940 until its flying component was redesignated in November 1942. It was established at Genzan in Korea, then part of the Empire of Japan, as a mixed formation containing both land-based bombers and fighter aircraft. Its initial equipment consisted of 33 Mitsubishi Type 96 G3M1 bombers and 25 Mitsubishi Type 96 A5M4 fighters. The group was initially subordinated to the Second Air Fleet and, in January 1941, was assigned to the 22nd Kōkū Sentai. The unit first saw sustained operations in China after moving to Hankou in central China. Its bomber element conducted strategic bombing missions against targets in Sichuan Province, while its fighter element performed combat air patrols and provided ground support for Imperial Japanese Army operations. The group returned to Genzan in September 1941 for training and was forward-deployed to Takao, Taiwan, near the end of October. Following the Japanese attack on Pearl Harbor and the wider opening of the Pacific War, Genzan moved to Saigon in French Indochina. On 10 December 1941, its aircraft participated in the Japanese attack that sank the British battleships HMS Prince of Wales and HMS Repulse off Malaya. The group lost one aircraft and its crew during that operation. In January 1942, its bombers attacked Kallang Airport in Singapore and supported Japanese advances in Malaya, including the landings at Endau. The group was subsequently moved through Bangkok, where inadequate facilities limited its usefulness, and then to Palembang in Sumatra. Some aircraft were also dispersed to Kuching in Sarawak. In May 1942, its flying component was redeployed to Rabaul in New Britain to support Japanese operations in New Guinea. It took part in the Battle of the Coral Sea and carried out repeated bombing attacks against Port Moresby, although the Coral Sea operation did not achieve its intended result. After the cancellation of Operation Mo, the group returned to Japan in July 1942 and was based at Misawa in Aomori for training. Its fighter element was separated and redesignated as the 252 Kōkūtai in September. The remaining flying unit was redesignated as the 755 Kōkūtai on 1 November 1942, ending the Genzan Air Group as an independent operational designation. The unit's wartime record illustrates the rapid movement of Japanese naval air formations between China, Southeast Asia, the Netherlands East Indies, and the South Pacific, as well as the severe attrition caused by daylight anti-shipping operations. A bomber associated with the group later conducted a damaging night torpedo attack on the aircraft carrier USS Intrepid on 19 February 1944.

The Genzan Air Group was formed on 15 November 1940 at Genzan, Korea, as a mixed Imperial Japanese Navy Air Service formation. Its original establishment included 33 Mitsubishi Type 96 G3M1 bombers and 25 Mitsubishi Type 96 A5M4 fighters. The unit initially operated under the Second Air Fleet and was assigned to the 22nd Kōkū Sentai on 15 January 1941. Its first operational theater was China. From Hankou, the bomber component conducted strategic bombing missions in Sichuan Province, while the fighter component flew combat air patrol and ground-support sorties connected with Japanese Army operations. The group left China in September 1941 and returned to Genzan for training before moving to Takao in Taiwan at the end of October. After the outbreak of the Pacific War, Genzan deployed to Saigon in French Indochina. On 10 December 1941, the group participated in the Japanese attack that sank HMS Prince of Wales and HMS Repulse off the coast of Malaya. It subsequently attacked Kallang Airport in Singapore and provided air support during the Japanese advance through Malaya, including operations connected with the Endau landings. At the end of February 1942, the group moved to Bangkok for Indian Ocean patrol duties. Because local facilities were considered inadequate, it soon transferred to Palembang in Sumatra, with some aircraft dispersed to Kuching in Sarawak. On 1 May, the flying unit moved to Rabaul in New Britain to support the Japanese campaign in New Guinea. It took part in the Battle of the Coral Sea and conducted repeated bombing missions against Port Moresby, but the Coral Sea operation did not produce the desired Japanese result. Following the cancellation of Operation Mo, the unit returned to Japan in July and undertook training from its base at Misawa in Aomori. The fighter element was detached and redesignated as the 252 Kōkūtai in September 1942. The remaining flying unit was redesignated as the 755 Kōkūtai on 1 November 1942, formally ending the Genzan Air Group designation. The unit's operational history reflects the Japanese use of mobile land-based naval aviation formations across widely separated theaters and the growing vulnerability of daylight anti-shipping missions. A bomber linked to the group later carried out a successful night torpedo attack that badly damaged USS Intrepid on 19 February 1944.

• 1944

  Night attack on USS Intrepid

  [1]Genzan Air Groupen.wikipedia.org

  A Rikko bomber associated with the group badly damaged USS Intrepid with a torpedo during a night attack on 19 February.

• 1942

  Singapore and Malaya operations

  [1]Genzan Air Groupen.wikipedia.org

  Genzan bombers attacked Kallang Airport and supported Japanese operations in Malaya.

• 1942

  Deployment to Rabaul

  [1]Genzan Air Groupen.wikipedia.org

  On 1 May, the flying unit moved to Rabaul to support Japanese operations in New Guinea and participated in the Battle of the Coral Sea.

• 1942

  End of the Genzan designation

  [1]Genzan Air Groupen.wikipedia.org

  The fighter unit became the 252 Kōkūtai in September, and the remaining flying unit became the 755 Kōkūtai on 1 November.

• 1941

  Assignment to the 22nd Kōkū Sentai

  [1]Genzan Air Groupen.wikipedia.org

  On 15 January, the group was reassigned from the Second Air Fleet structure to the 22nd Kōkū Sentai and deployed to Hankou.

• 1941

  China operations

  [1]Genzan Air Groupen.wikipedia.org

  The group conducted bombing, patrol, and ground-support operations from Hankou before withdrawing to Genzan in September.

• 1941

  Forward deployment to Takao

  [1]Genzan Air Groupen.wikipedia.org

  The unit moved to Takao in Taiwan at the end of October in preparation for wider Pacific War operations.

• 1941

  Attack on British capital ships

  [1]Genzan Air Groupen.wikipedia.org

  On 10 December, Genzan aircraft participated in the attack that sank HMS Prince of Wales and HMS Repulse off Malaya.

• 1940

  Formation at Genzan

  [1]Genzan Air Groupen.wikipedia.org

  The Genzan Air Group was established on 15 November at Genzan in Korea as a mixed bomber and fighter formation.

A mobile Imperial Japanese naval aviation formation combining bomber, fighter, patrol, ground-support, and airbase-garrison functions.

• Land-based naval bomber

  Mitsubishi Type 96 G3M1

  The Genzan Air Group was initially equipped with 33 Mitsubishi Type 96 G3M1 bombers. These long-range land-based naval aircraft formed the group's principal strike element and were used for strategic bombing, maritime attack, and support of Japanese operations across China, Southeast Asia, and the South Pacific.

• Carrier-capable fighter aircraft used in land-based operations

  Mitsubishi Type 96 A5M4

  Twenty-five Mitsubishi Type 96 A5M4 fighters were part of the group's original mixed establishment. They performed combat air patrol, local defense, and ground-support duties during the unit's China and early Pacific War deployments before the fighter element was detached and redesignated as the 252 Kōkūtai.

• Long-range naval bomber

  Rikko bomber

  A Rikko bomber associated with the unit carried out a night torpedo attack against USS Intrepid in February 1944. The aircraft type was used for long-range maritime strike and bombing missions by Japanese naval aviation formations.

• 1942Singapore and Malaya support operations

  Singapore · Malaya

  The group attacked Kallang Airport on 22 January and supported Japanese offensives in Malaya, including the Endau landings.

  Outcome. The unit continued its southward redeployment after the Malayan operations.

  Source
• 1942New Guinea and Coral Sea operations

  New Guinea · Coral Sea · Port Moresby

  After moving to Rabaul on 1 May, Genzan supported Japanese operations in New Guinea, participated in the Battle of the Coral Sea, and conducted bombing attacks against Port Moresby.

  Outcome. The Battle of the Coral Sea did not achieve the intended Japanese result, and the unit returned to Japan after Operation Mo was cancelled.

  Source
• 1941China operations

  China

  From Hankou, Genzan bombers conducted strategic bombing missions in Sichuan Province, while its fighters flew patrol and ground-support missions in support of Japanese Army operations.

  Outcome. The unit withdrew from China in September 1941 and returned to Genzan for training.

  Source
• 1941Malaya naval campaign

  Malaya · South China Sea

  Genzan aircraft participated in the 10 December attack on HMS Prince of Wales and HMS Repulse.

  Outcome. Both British capital ships were sunk, while Genzan lost one aircraft and its crew.

  Source

• 1942

  Shift toward night anti-shipping tacticsStrategy

  Background

  Daylight anti-shipping bombing missions caused heavy losses among Japanese air groups, encouraging a broader move toward night operations.

  Action taken

  The unit's operational experience contributed to the transition toward night bombing and torpedo tactics, later illustrated by the attack on USS Intrepid.

  Aftermath

  A bomber associated with Genzan badly damaged USS Intrepid in a night torpedo attack on 19 February 1944.

  Source

• 1942

  Return to Japan for trainingStrategy

  Background

  After the cancellation of Operation Mo and the completion of its Rabaul-area operations, the group was withdrawn from the South Pacific.

  Action taken

  The unit returned to Japan in July and was based at Misawa, Aomori, for training.

  Aftermath

  The fighter and bomber components were subsequently reorganized under separate designations.

  Source

• 1942

  Redesignation and dissolution of the unitOther

  Background

  The Imperial Japanese Navy reorganized its air groups during the Pacific War.

  Action taken

  The fighter element became the 252 Kōkūtai in September, and the remaining flying unit became the 755 Kōkūtai on 1 November.

  Aftermath

  The Genzan Air Group ceased to exist as an independent designation.

  Source

1. 1Genzan Air Groupen.wikipedia.org