Japanese aircraft carrier Zuikaku

In May 1942, she was assigned along with Shōkaku to support Operation Mo, the invasion of Port Moresby, New Guinea. Alerted by intercepted and decrypted Japanese naval messages, the Americans dispatched the carriers USS Yorktown and Lexington to stop this operation. On 8 May 1942, during the Battle of the Coral Sea, the main carrier forces located one another and launched maximum-effort raids, which passed each other in the air. Hidden by a rain squall, Zuikaku escaped detection, but Shōkaku was hit three times by bombs and was unable to launch or recover her aircraft. In return, torpedo and dive bombers from both ships hit Lexington, which was later scuttled by torpedoes from an escorting destroyer. Zuikaku was undamaged in the battle, but sustained severe losses in aircraft and aircrew. This required her to return to Japan with her sister ship for resupply and aircrew training, and neither carrier was able to take part in the Battle of Midway in June 1942, where every carrier that participated in the Pearl Harbor attack besides the two Shōkaku class ships were sunk by American carrier based aircraft.

In August 1942, commanded by Captain Tameteru Notomo, Zuikaku was dispatched as part of the First Carrier Division along with the repaired Shōkaku and the light carrier Zuihō to oppose the American offensive in the Solomon Islands. On 24 August 1942, in the Battle of the Eastern Solomons, her aircraft severely damaged the carrier USS Enterprise. She was based at Truk for the next few months.

On 26 October 1942, in the Battle of the Santa Cruz Islands, her aircraft again damaged the repaired Enterprise, and crippled USS Hornet (Hornet was abandoned after a failed scuttling attempt and later sunk by Japanese destroyers). However, Shōkaku and Zuihō were both severely damaged by American air attacks, and Zuikaku had to recover their surviving aircraft in addition to her own. Of the 110 aircraft launched by the three Japanese carriers, only 67 returned to Zuikaku. She then returned to the home islands via Truk for training and aircraft ferrying duties.

Zuikaku cruising toward Hitokappu Bay, Iturup, in November 1941. The carrier Kaga is seen in the background.

In February 1943, she covered the evacuation of Japanese ground forces from Guadalcanal. In May, she was assigned to a mission to counterattack the American offensive in the Aleutian Islands, but this operation was cancelled after the Allied victory on Attu on 29 May 1943. Later in 1943, under the command of Captain Kikuchi Tomozo, she was again based at Truk and operated against U.S. forces in the Marshall Islands.

In 1944, she was based at Singapore. In June, she was assigned to Operation A-Go, an attempt to repulse the Allied invasion of the Mariana Islands. On 19 June, in the Battle of the Philippine Sea, Taihō and Shōkaku were both sunk by American submarines, leaving Zuikaku, the only survivor of Carrier Division One, to recover the Division's few remaining aircraft. On 20 June, a bomb hit started a fire in the hangar, but Zuikaku's experienced damage control teams managed to get it under control, and she was able to escape under her own power. After this battle, Zuikaku was the only survivor of the six fleet carriers that had launched the attack on Pearl Harbor.

Zuikaku and destroyer Wakatsuki underway during U.S. carrier plane attacks. The carrier Zuiho is in the background.

In October 1944, she was the flagship of Admiral Jisaburo Ozawa's decoy Northern Force in Operation Shō-Gō 1, the Japanese counterattack to the Allied landings on Leyte. On 24 October, as part of the depleted (just 108 aircraft across six carriers) Third Carrier Division, she launched aircraft along with the light carriers Zuihō, Chitose, and Chiyoda in an ineffective strike against the U.S. Third Fleet. Several of these aircraft were shot down, and the majority of the surviving aircraft did not return to the carriers, instead landing at Japanese land bases on Luzon. However, some of her aircraft made kamikaze attacks and helped sink the light carrier USS Princeton; and most of the others were sent to other surviving carriers and air bases, to later sink the escort carrier USS St. Lo during the Battle off Samar after again using the new kamikaze tactics.

The next day, during the Battle off Cape Engaño, she launched her few remaining aircraft for combat air patrol, search, or to join the aircraft already on Luzon. She then came under heavy air attack and was hit by seven torpedoes and nine bombs. With Zuikaku listing heavily to port, Ozawa shifted his flag to the light cruiser Ōyodo. The order to abandon ship was issued at 13:58 and the naval ensign was lowered. Zuikaku rolled over and sank stern-first at 14:14, taking the lives of Rear Admiral (promoted from captain 10 days earlier) Kaizuka Takeo and 842 of the ship's crew; 862 officers and men were rescued by the destroyers Wakatsuki and Kuwa. Zuikaku was the last surviving Japanese carrier to have attacked Pearl Harbor before her loss. She was also the only Japanese fleet carrier (as opposed to a light carrier) to have been sunk by aircraft-launched torpedoes, as all others were sunk by dive bombers or submarine-launched torpedoes.[2]