The Battle of the Philippine Sea or マリアナ沖海戦 in Japanese, was a major naval battle that occurred concurrently with Mariana Islands campaign. The Battle was nicknamed by US Navy pilots the 'Great Marianas Turkey Shoot' due to the losses suffered by the IJN pilots. One pilot from the USS Lexington CV-16 would later exclaim "Why, hell, it was just like an old-time turkey shoot down home!".
On 12 June 1944, the US Navy began launching Carrier Strikes on the Mariana Islands. This surprised the IJN, which had expected an attack on the Caroline Islands or the Palaus. As a result, Operation A-GO was initiated, with the goal of attacking the US Carriers near the Marianas. The Main carrier force of the Japanese forces included the newly commissioned IJN Taihō, which was the flagship of Vice-Admiral Jisaburo Ozawa. IJN Shōkaku and Zuikaku were also assigned to the Carrier Group.
On 15 June, USS Flying Fish SS-229 (a Gato-class Submarine) spotted a Japanese fleet leaving the San Bernardino Strait in the Philippines. An Hour later, the USS Seahorse SS-304 (a Balao-class Submarine) spotted another Japanese fleet east of the Island of Mindanao. With news of a Japanese fleet approaching, Admiral Marc Mitscher was ordered to move Task Force 58 (the Fast Carrier Task Force) to west of Saipan into the Philippine Sea.
