601st Naval Air Group

The 601st Naval Air Group was a Japanese naval aviation formation active during the Pacific campaign of the Second World War. Its Japanese designation was Dai Roku-Maru-Hito Kaigun Kōkūtai. Unlike a commercial brand, it was a military organization within the Imperial Japanese Navy Air Service, responsible for operating and administering naval aircraft and their personnel in carrier-based and later land-based roles. The unit was established on 15 February 1944 and initially came under the 3rd Fleet. Its first commander was Commander Irisa Toshiie, who also served as air officer aboard the aircraft carrier Taihō. The group’s early organization reflected the Imperial Japanese Navy’s carrier-air-group system, in which fighter, attack, and reconnaissance squadrons were associated with a carrier division or fleet formation. The 601st therefore functioned as an operational aviation unit rather than as a permanent territorial air base. The group’s early wartime history was closely connected with Taihō. On 19 June 1944, during the Battle of the Philippine Sea, Taihō was sunk and Irisa was killed. He was subsequently promoted two ranks posthumously. The group’s command remained vacant until 10 July 1944, when Commander Suzuki Masakazu assumed leadership. On that date the 601st was transferred to the 1st Carrier Division. Its listed subordinate elements included the 161st and 162nd Fighter Squadrons, the 161st and 262nd Attack Squadrons, and the 61st Reconnaissance Squadron. Several of these formations remained attached only until November 1944, reflecting the frequent restructuring of Japanese naval air units as carrier aviation suffered severe personnel and aircraft losses. From 10 February 1945, the 601st was placed under the 3rd Air Fleet and was reorganized primarily as a land-based formation. Its listed subordinate units included the 308th and 310th Fighter Squadrons, the 1st Attack Squadron, and the 254th Attack Squadron, while the 402nd Fighter Squadron was attached for part of March and April. This reorganization represented the broader wartime shift of Japanese naval air power away from effective carrier operations and toward the defense of land bases and the Japanese homeland. The group was commanded during this final phase by Commander Sugiyama Toshikazu, who became a captain on 1 May 1945. The 601st Naval Air Group remained under the 3rd Air Fleet through the end of the war. Sugiyama was its commanding officer when Japan accepted the Allied surrender on 15 August 1945. The unit did not continue as an active postwar organization. Its historical importance lies in its connection to the late-war Imperial Japanese Navy carrier-air system, the loss of Taihō and experienced naval aviators in 1944, and the subsequent conversion of a carrier-oriented formation into a land-based garrison and air-combat unit.

The 601st Naval Air Group was an Imperial Japanese Navy Air Service formation created on 15 February 1944. It began under the 3rd Fleet and was structured as a carrier air group, bringing together fighter, attack, and reconnaissance elements for naval aviation operations. Its first commander was Commander Irisa Toshiie, who simultaneously served as air officer of the aircraft carrier Taihō. The group’s initial history was shaped by the crisis of Japanese carrier aviation in 1944. On 19 June, Taihō was sunk during the Battle of the Philippine Sea and Irisa was killed. He received a posthumous two-rank promotion. Command of the 601st remained vacant until 10 July, when Commander Suzuki Masakazu took over. The same date marked the group’s transfer to the 1st Carrier Division. Its organization then included the 161st and 162nd Fighter Squadrons, the 161st and 262nd Attack Squadrons, and the 61st Reconnaissance Squadron. The 161st and 162nd Fighter Squadrons, the 161st Attack Squadron, the 262nd Attack Squadron, and the 61st Reconnaissance Squadron were subsequently removed from the listed organization during November 1944. On 10 February 1945, the unit was transferred to the 3rd Air Fleet and converted into a land-based garrison and air-combat formation. Its later organization included the 308th and 310th Fighter Squadrons and the 1st Attack Squadron. The 254th Attack Squadron was attached from 20 February to 5 March, and the 402nd Fighter Squadron from 5 March to 20 April. These changes illustrate the fluid administrative structure of Japanese naval air units in the final phase of the war, when carrier-based aviation formations were increasingly redirected to land bases and homeland defense. Commander Suzuki led the unit until 10 February 1945. He was succeeded by Commander Sugiyama Toshikazu, who became a captain on 1 May 1945. Sugiyama remained in command through 15 August 1945, the date associated with Japan’s acceptance of surrender. The 601st Naval Air Group did not survive as an active postwar organization. Its record is preserved through Japanese naval administrative documents, military histories, and studies of Imperial Japanese Navy aircraft, carriers, unit markings, and wartime organization.

• 1945

  Conversion to a land-based formation

  [1]601st Naval Air Groupen.wikipedia.org

  On 10 February, the group came under the 3rd Air Fleet and was reorganized as a land-based garrison and air-combat unit.

• 1945

  End of wartime service

  [1]601st Naval Air Groupen.wikipedia.org

  The unit remained under the 3rd Air Fleet through Japan’s surrender on 15 August 1945.

• 1944

  Formation of the 601st Naval Air Group

  [1]601st Naval Air Groupen.wikipedia.org

  The unit was established on 15 February 1944 under the Imperial Japanese Navy’s 3rd Fleet.

• 1944

  Loss of commander Irisa Toshiie

  [1]601st Naval Air Groupen.wikipedia.org

  Irisa was killed on 19 June 1944 when the carrier Taihō sank. He was posthumously promoted two ranks.

• 1944

  Transfer to the 1st Carrier Division

  [1]601st Naval Air Groupen.wikipedia.org

  On 10 July, the group moved from the 3rd Fleet structure to the 1st Carrier Division under Commander Suzuki Masakazu.

A late-war Imperial Japanese Navy aviation formation, initially organized for carrier operations and later employed as a land-based air and garrison unit.

• 1944Pacific campaign

  The 601st Naval Air Group participated as an Imperial Japanese Navy aviation formation during the Pacific campaign. Its wartime role shifted from carrier-associated operations to land-based defense as Japanese naval aviation was reorganized.

  Outcome. The group was ultimately retained under the 3rd Air Fleet until the end of the war and then became defunct.

  Source

• 1945

  Conversion from carrier air group to land-based unitStrategy

  Background

  After the group’s carrier-era organization and the severe attrition affecting Japanese naval aviation, the Imperial Japanese Navy reorganized it under the 3rd Air Fleet.

  Action taken

  On 10 February 1945, the 601st was placed under the 3rd Air Fleet and operated as a land-based garrison and air-combat formation.

  Aftermath

  The unit continued with fighter and attack squadrons until Japan’s surrender in August 1945.

  Source

1. 1601st Naval Air Groupen.wikipedia.org
2. 2Japan Center for Asian Historical Recordsjacar.go.jp