Battle of the Philippine Sea (1944): The Marianas Turkey Shoot

The Battle of the Philippine Sea, fought on 19 and 20 June 1944 west of the Mariana Islands, was the largest aircraft carrier battle in history. During the US invasion of Saipan, Admiral Raymond Spruance’s Fifth Fleet and its Task Force 58 met a Japanese carrier force under Vice Admiral Jisaburō Ozawa. In a single day American pilots and gunners destroyed most of Japan’s carrier aircraft in what they called the “Great Marianas Turkey Shoot”, and Japanese naval aviation never recovered.

Background: the invasion of the Marianas

By mid-1944 the United States was advancing across the central Pacific. The Mariana Islands, including Saipan, Tinian and Guam, lay within bombing range of the Japanese home islands for the new B-29 Superfortress. Operation Forager, the invasion of the Marianas, began with landings on Saipan on 15 June 1944.

Japan’s naval leaders had been rebuilding their carrier force since its heavy losses at the Battle of Midway in 1942 and in the Solomons. Under Operation A-Gō they planned a decisive battle in the western Pacific. When the Americans landed on Saipan, Ozawa’s Mobile Fleet sailed to destroy the US fleet, counting on land-based aircraft on Guam and on the longer range of Japanese carrier planes.

The opposing forces

Task Force 58, under Vice Admiral Marc Mitscher, had 15 aircraft carriers (seven fleet carriers and eight light carriers), seven fast battleships and about 900 aircraft. It was supported by an extensive radar and fighter-direction system and by new Grumman F6F Hellcat fighters flown by well-trained pilots.

The quality gap was as important as the numbers. US Navy pilots typically arrived at the front with two years of training and some 300 or more flying hours, while many Japanese replacements had well under half that. The Hellcat was faster in a dive, better armed and far better protected than the Mitsubishi A6M Zero, and American ships carried large numbers of anti-aircraft guns, some firing shells with the new proximity fuze.

Ozawa had nine carriers (five fleet carriers and four light carriers) with around 430–450 aircraft, plus five battleships including Yamato and Musashi. Many of his pilots, however, had only a few months of training, because the experienced aircrews of 1941–1942 had largely been killed in earlier battles. Japanese land-based air power in the Marianas had already been badly damaged by American carrier raids.

19 June: the Turkey Shoot

On the morning of 19 June Ozawa launched four large air raids against Task Force 58. American radar detected them at long range, and Hellcats directed by fighter controllers met them well before they reached the carriers. Most of the attackers were shot down; the few that got through scored only a bomb hit on the battleship South Dakota and some near misses.

Ozawa had hoped to exploit the longer range of his aircraft by launching from a distance the Americans could not reach, with his planes landing on Guam to refuel and rearm before attacking again. The plan depended on airfields that American raids had already wrecked, and on aircrews skilled enough to find and hit a well-defended fleet hundreds of kilometres away.

US fighters also attacked aircraft over Guam, where many Japanese planes were trying to land. By the end of the day Japan had lost roughly 300–350 aircraft, while the Americans lost about 30. One US pilot’s remark that it was like an old-time turkey shoot gave the day its famous name.

The same day American submarines struck the Japanese carriers. USS Albacore torpedoed the new armoured carrier Taihō, Ozawa’s flagship, which later blew up because of a petrol vapour explosion. USS Cavalla hit the Shōkaku, a veteran of Pearl Harbor, which also exploded and sank with heavy loss of life.

20 June: the mission beyond darkness

Spruance kept Task Force 58 near the Marianas on 19 June to guard the Saipan beachhead, then moved west to find the retreating Japanese fleet. Late on the afternoon of 20 June search planes finally located it at the edge of American range. Mitscher launched an attack by about 220 aircraft, knowing that they would return after dark.

The strike sank the carrier Hiyō and two oilers and damaged Zuikaku, Chiyoda and other ships. On the return flight, many planes ran short of fuel. Mitscher ordered his carriers to turn on their lights, risking submarine attack, to guide the pilots home. About 80 aircraft were lost through ditching or crash landings, but rescue efforts over the following days recovered most of the crews.

Key people

• Raymond Spruance, commander of the US Fifth Fleet, who put the protection of the invasion first.
• Marc Mitscher, commander of Task Force 58, a pioneer of naval aviation, remembered for lighting up his carriers on the night of 20 June.
• Jisaburō Ozawa, commander of the Japanese Mobile Fleet, a capable admiral who later led the decoy force at Leyte Gulf.

By the numbers

Consequences

The battle left Japan with carriers but almost no trained aircrews to fly from them. Saipan fell on 9 July 1944, Guam and Tinian soon after, and the loss of Saipan led to the resignation of Prime Minister Hideki Tōjō’s cabinet on 18 July. From airfields in the Marianas, B-29 bombers began raiding Japan in November 1944, leading to the devastating firebombing of Tokyo in March 1945. The atomic bombs were later flown to Japan from Tinian.

The fighting on land was ferocious. Most of the Japanese garrison of Saipan, around 30,000 men, died, and the Americans suffered more than 3,000 dead. Many Japanese civilians on the island also died, some of them by suicide at the cliffs at the northern tip of the island rather than surrender, a tragedy that foreshadowed the battle for Okinawa.

When Japan’s navy fought again in October 1944, at the Battle of Leyte Gulf, its surviving carriers had so few aircraft that they could serve only as a decoy. The lack of skilled pilots also encouraged Japanese commanders to turn to suicide tactics.

Legacy

Spruance’s caution was criticised at the time by some naval aviators, who felt he had missed the chance to destroy the whole Japanese fleet. Spruance himself accepted the criticism calmly and never changed his view that his first duty was to the troops ashore. Most historians now judge that the decision to protect the landings was sound, since the Japanese carrier force had been rendered almost useless anyway. The battle is often cited as the clearest demonstration of how training, radar and industrial strength combined to give the United States overwhelming superiority at sea.

Timeline

• 1944, 11–14 June: US carrier raids on the Marianas.
• 1944, 15 June: US Marines land on Saipan.
• 1944, 19 June: Great Marianas Turkey Shoot; Taihō and Shōkaku are sunk by submarines.
• 1944, 20 June: US late-afternoon strike sinks Hiyō; aircraft return after dark.
• 1944, 9 July: Saipan is declared secured.
• 1944, 18 July: Tōjō’s cabinet resigns.

Why it matters

The Battle of the Philippine Sea broke Japan’s carrier air arm, opened the way for the strategic bombing of Japan and showed that the United States now held complete command of the Pacific.