ROKS Baekdusan with South Korean flag painted on the side of the ship's superstructure in the 1950s
History
United States
Name	PC-823
Builder	Leathem D. Smith Shipbuilding Company
Laid down	8 November 1943
Launched	15 January 1944
Commissioned	24 July 1944
Decommissioned	11 February 1946
Stricken	Transferred to United States Merchant Marine Academy, June 1948
Renamed	Ensign Whitehead
Fate	Transferred to South Korea, September 1949
South Korea
Name	Pak Tu San
Namesake	Paektu Mountain
Acquired	17 October 1949
Commissioned	26 December 1949
Decommissioned	21 August 1960
Identification	Hull number: PC-701
Fate	Presumed scrapped
Notes	Mast preserved at Republic of Korea Navy Academy
General characteristics
Class and type	PC-461
Displacement	280 tons
Length	173 ft 8 in (52.93 m)
Beam	23 ft 0 in (7.01 m)
Draft	10 ft 10 in (3.30 m)
Speed	20 knots
Complement	65
Armament	1 × 3 in (76 mm)/50 cal 6 × .50 caliber machine guns 4 × depth charge throwers 2 × depth charge tracks 2 x depth charge projector (Mousetrap).

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.

PC-823 served in the western Atlantic Ocean during World War II, being assigned to air-sea rescue duties during at least some of that time. On 11 February 1946, PC-823 decommissioned and transferred to the United States Maritime Commission. 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. Her name was struck from the Navy List in June 1948.

In September 1949, she was transferred to the Republic of Korea Navy and renamed ROKS Pak Tu San, (PC-701), and played a major part in the Battle of Korea Strait, the small naval battle fought on the first day of the Korean War in June 1950. The remains of her mast are kept in the South Korean naval academy.

Upon its establishment on 11 November 1945, the South Korean navy (ROKN) had only LCVPs and light wooden patrol ships at its disposal. The ROKN's first Chief of Naval Operations, Admiral Sohn Won-yil, emphasized the necessity of acquiring a new naval vessel. However, as the South Korean government could not provide either the natural resources or economic means available to purchase new ships, the ROKN decided on an independent purchase of a new vessel and organized the "Vessel Construction Finance Committee"(함정건조 각출위원회) in June 1949. 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. After four months, the ROKN managed to raise $15,000. The South Korean government provided an additional $45,000 upon hearing of the ROKN's efforts, summing for a total of $60,000.

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. Upon its purchase, the ship was initially in such a poor condition that it had to go through two months of repairs by fifteen naval officers. On 26 December 1949 in New York, the Ensign Whitehead was launched and christened as the ROKS Pak Tu San (PC-701), the ROKN's first ocean-going vessel. Sailing from New York, a 3-inch main deck gun was attached at the Pearl Harbor Naval Shipyard, and 100 shells were purchased at Guam. 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. The PC-701 challenged the ship using signal lights, but receiving no response, turned its searchlight on the intruder. The light revealed a 1,000 ton freighter with an estimated six hundred to one thousand soldiers crowded on her decks. Heavy machine guns were mounted aft on the freighter with which the freighter crew opened fire on the PC-701. The gunfire struck her bridge, killing the helmsman and seriously wounding an officer on the deck. She returned fire and engaged in a running duel with the freighter. According to veterans of the PC-701, to increase the accuracy and penetration, PC-701 closed to within 400 meters of the freighter. The sailors had to use their M1 Garands to prevent North Korean soldiers from swimming to the PC-701. The freighter was sunk between Busan and Tsushima Island. This action, which would later become known as the Battle of Korea Strait, was the first naval engagement of the ROKN.

After Battle of Korea Strait, the ROKS Pak Tu San saw combat during various other battles of the Korean War, such as the Incheon Landing.

After the war, the ROKS Pak Tu San retired on 1 July 1959, and was subsequently dismantled.

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. The poor state of combat readiness at the port could easily have led to its loss. In such an event, not even the small toehold of Busan would have remained to support the U.N. counteroffensive in Korea. This single naval action may well have prevented the fall of South Korea.

Her mast is preserved at Republic of Korea Navy Academy.

• NavSource Online:Submarine Chaser Photo Archive PC-823

• Photo gallery at navsource.org