During 1944 and 1945, Vice Admiral Mitscher's fast carriers, whether designated Task Force 38 or Task Force 58, spearheaded the thrust against the heart of the Japanese Empire, covering successively the invasion of the Palaus, the liberation of the Philippines, and the conquests of Iwo Jima and Okinawa. On 26 January 1945, the Third Fleet again became the Fifth Fleet. During the Okinawa operation there was a weather-caused delay in the Army preparing serviceable air bases. To provide essential air support to the intense ground operations, Mitscher was obliged to keep then-Task Force 58 sailing in a box on station some east of Okinawa, often in stormy weather and heavy seas, for the next two months. During this time they were subject to air attack around the clock, and the psychological pressures of warding off these attacks were enormous. Rarely did a night go by that all the ships' crews were not called to general quarters, and the days were worse.