A decisive two-day World War II naval engagement on 19–20 June 1944 that destroyed Japanese carrier air power, drastically shifting Pacific theater dominance to the United States.
American fast carrier task forces launched preliminary strikes against Japanese airfields on Guam and Saipan, destroying dozens of enemy aircraft to secure local air superiority ahead of the main battle.
Vice Admiral Jisaburō Ozawa led the Japanese Mobile Fleet from Tawi-Tawi toward the Philippine Sea, aiming to attack the US invasion fleet supporting the Saipan landings.
US Marines landed on Saipan, triggering the Japanese plan for a decisive naval counterattack that would culminate in the Battle of the Philippine Sea.
Admiral Raymond Spruance commanded the US Fifth Fleet to maintain a defensive position west of Saipan, prioritizing protection of the invasion beaches over pursuing the Japanese fleet.
A second Japanese raid of over 100 aircraft was largely destroyed by American combat air patrols, with only a handful of bombers penetrating the defensive screen to cause minor damage.
The USS Albacore torpedoed the flagship Taihō, Japan's newest and most advanced carrier; flawed damage control led to a massive explosion later that afternoon.
The USS Cavalla torpedoed and sank the Japanese carrier Shōkaku, one of the veterans of the Pearl Harbor attack, dealing a major blow to Ozawa's fleet.
By the end of the day, Japan lost approximately 315 aircraft and two carriers to American fighters and submarines, effectively breaking the back of their naval air arm.
The first Japanese strike of 69 aircraft was detected by US radar, allowing American fighters to intercept and decimate the unescorted bombers before they could reach the fleet.
Ozawa launched reconnaissance aircraft at dawn to locate the American fleet, while Japanese carriers began preparing their first massive airstrike of the engagement.
Fumes from ruptured aviation fuel tanks accumulated below decks on the Taihō and ignited, destroying the carrier and killing over 1,600 crewmen including Ozawa's staff.
The third Japanese strike failed to locate the American fleet and jettisoned their ordnance, while a fourth wave mistakenly attacked US picket destroyers without scoring significant hits.
Over 200 American aircraft from 11 carriers set off toward the retreating Japanese fleet, facing dwindling fuel and fading daylight as they pursued the enemy westward.
An American search plane finally sighted the Japanese fleet at extreme range, prompting Admiral Marc Mitscher to launch a massive strike despite the risk of a dangerous night recovery.
American dive bombers and torpedo planes struck the Japanese fleet, sinking the carrier Hiyō and damaging carriers Chiyoda, Zuikaku, and Jun'yō along with a battleship.
Returning American pilots faced a perilous night landing on US carriers; Admiral Mitscher ordered lights illuminated despite submarine risks, saving many crews but losing many aircraft to crashes.
The Japanese fleet retreated to Okinawa, having lost three carriers and approximately 400 aircraft in two days, permanently crippling its capacity for large-scale carrier operations.
The decisive victory ensured the safety of the Saipan invasion force and confirmed US naval supremacy in the Pacific, paving the way for the liberation of the Philippines.