"YW-56" was renamed "Moosehead", the second U.S. Navy ship of that name, and reclassified IX-98 on 13 February 1943. Following installation of sonar and radar equipment, she commissioned at San Diego on 5 April 1943, Lt. D. J. Spahr in command. She reported for duty with the Operational Training Command, Pacific Fleet, 11 April, and on 23 April she became the flagship of Rear Admiral Frank A. Braisted, COTCPac. During the remaining years of World War II "Moosehead" operated out of San Diego.