The Battle of the Philippine Sea, 1944

The Naval Battle of the Philippine Sea, June 19–20, 1944, a major carrier engagement with the Japanese Imperial Navy, took place during the U.S. amphibious invasion of Saipan and Mariana Islands. It was the greatest carrier battle in history.

Japan regarded the Marianas, including Saipan, Guam, and Tinian, as part of her homeland in addition to being integral to her inner defense perimeter. Its land-based fighter and bomber aircraft on these islands controlled the sea lanes to Japan and protected the home islands. However, in late 1943 Japan's outer defensive ring was overrun at the costly Battle of Tarawa, and in early 1944, the U.S. fleet had pressed on through the Marshall Islands sweeping across other islands in the Central Pacific. For the Americans, control of the Marianas would put the Japanese homeland within range of American bombers. An attack on  the Marianas, however, inevitably would bring on a naval battle with the Japanese.

From June 13-15, 1944, U.S. carriers began a series of air strikes on the Marianas, convincing the Japanese that the Americans were preparing to invade. This move came as a surprise to the Japanese as they had expected the next U.S. target to be farther to the south, either the Carolines or the Palaus. This belief led to their fortification of these islands with less preparation given to the possibility of a Marianas invasion. Saipan D-day came on June 15 when American Marines invaded in an amphibious landing.

The Japanese immediately ordered a counterattack by sea, committing nearly all of its serviceable ships to the engagement. Their force consisted of 9 carriers and 5 battleships. Their plan was to bring on a decisive battle while their ground forces on Saipan fought off the American invasion.

Battle of the Philippine Sea, June 19-20, 1944
Source: Wikimedia Commons

On today's date in 1944, the Japanese began their air attack against the U.S. Navy's Fifth Fleet. They launched 4 separate raids. In what is remembered by American sailors and airmen as the first day of the "Marianas Turkey Shoot," the Japanese lost more than 240 planes, the Americans only 30. Damage to American ships was also minimal, with damaged battleship, USS South Dakota, able to remain in the fight. Two American submarines, the Albacore and Cavalla, each sunk an enemy carrier.

The next day, with only about 200 aircraft left, the Japanese continued their attacks. By the afternoon, the Americans had verified the Japanese fleet's position and launched an all-out attack of their own. Approaching the enemy's ships, the American pilots encountered intense antiaircraft fire. Nevertheless, they were able to press their attack, sinking another carrier and damaging 2 more, along with a battleship. Japanese naval power had suffered irreparable damage.

The return trip for the American pilots was a harrowing experience. The distance involved required most of the aircraft to run dangerously low on fuel, while nighttime had fallen. Carriers were illuminated to help the returning pilots find their way, despite the risk of enemy submarine and air attacks. Eighty of the returning planes were lost, some crashing on flight decks, while the majority went into the sea. Thankfully, most of their crews were rescued over the next few days.

Overnight, the Japanese fleet withdrew. By the battle's conclusion, the Japanese had lost 3 carriers, 2 oilers, and more than 600 carrier- and land-based aircraft. As much as 90% of the Japanese carrier aviation force was destroyed in 2 days. The Americans lost 123 aircraft and some damage to ships. Amazingly, only 16 pilots and 33 aircrew remained missing by the end of the engagement.

So decisive was the Battle of the Philippine Sea for the Americans that it eliminated the Imperial Japanese Navy's ability to conduct large-scale carrier actions for the remainder of the war. In that battle the Japanese Navy lost the majority of its carrier air strength.  It would never recover.

Source: The Two-Ocean War, Samuel Eliot Morrison