USS PC-823 PC-461-class submarine chaser laid down on 2 June 1943 at the Leathem D. Smith Shipbuilding Company in Sturgeon Bay, Wisconsin; launched on 15 January 1944; and commissioned on 24 July 1944.

She was transferred to the United States Merchant Marine Academy at Kings Point, New York on 18 May 1948, and renamed Ensign Whitehead as a training ship.

From top officers to cadets, ROKN servicemen invested 5%~10% of their salaries to fund the purchase, with some midshipmen and their wives selling scrap metal and taking in laundry and sewing.

On 17 October 1949, South Korea acquired the Ensign Whitehead (the former USS PC-823), then a training ship of the United States Merchant Marine Academy.

PC-701 finally arrived at Jinhae Naval Base, South Korea, on 10 April 1950, barely two months before the June 1950 outbreak of the Korean War.

On the night of 25 June 1950, the Pak Tu San's crew spotted an unidentified ship on the South Korean eastern coast, about twenty miles from the key port of Busan, during a patrol mission.

[4] Except for the fortuitous position of the PC-701 and the fighting qualities of the craft's crew, the North Korean soldiers might have successfully landed at the vital port of Busan.