page_title: Blockade of Wonsan
section_title: April 1952
hierarchical_section_title: Blockade of Wonsan / Blockade / Escalation of the naval war / April 1952
caption_attribution_description: English: The U.S. Navy destroyer USS George K. MacKenzie (DD-836) off Point Loma, California (USA), circa in the early 1970s.
context_page_description: The Blockade of Wonsan, or the Siege of Wonsan, from February 16, 1951 to July 27, 1953, during the Korean War, was the longest naval blockade in modern history, lasting 861 days. UN naval forces, primarily from the United States, successfully kept the strategically important city of Wonsan from being used by the North Korean Navy.
  The blockade diverted communist troops from the front line. North Korean artillery fired at the American fleet was mostly ineffective, and the city was heavily damaged by UN naval aircraft and warships.
context_section_description: USS Leonard F. Mason experienced an explosion in the depth charge starboard detonator locker on April 1, while bombarding Ho-do Pan-do, no casualties were reported. Wiltsie, USS McGinty, and USS Condor were also engaged in the action. USS Symbol, USS Murrelet and USS Edmonds received enemy fire near Wonsan on April 2 and again no damage or casualties were experienced. The same day USS Wiltsie received ten near misses from shore batteries east of Kalmagak while providing fire support for Condor. Wiltsie was attacked a few more times within the next several days and they were all inconclusive contacts.
  In the Wonsan area on April 10, TF-77 carried out a coordinated strike using the guns of USS Saint Paul and USS Hanson. USS Silverstein, to the north of Ho-do Pan-do, received 30 rounds of enemy fire at a range of 12,400 yards (11,300 m) with fall of shot 50 to 300 yards (46 to 274 m) from the ship but without damaging her. The incident was taken as evidence that the North Koreans were beginning to use fire control more regularly. On April 11, Wiltsie and McGinty were taken under fire by Wonsan shore batteries. Both ships conducted maneuvers in separate areas and delivered counter battery fire.
  Silverstein, USS Cabildo and USS Apache fired suppression fire against the batteries on Ho-do Pan-do. McGinty was straddled by enemy shore batteries as she moved near Wonsan on April 17. McGinty and USS Maddox replied with counter fire and the enemy guns ceased. USS Cabildo was attacked again from shore batteries on April 29 from Ho-do Pan-do. Three near misses straddled ship and one direct hit amidships caused minor damage to structure and electrical wiring, two were wounded.
  On the same day, USS Silverstein and USS Maddox, in a swept area south of Yo-do, were covering the withdrawal of two friendly sampans from Umi-do, when suddenly enemy batteries opened fire. The sampans received the first salvos, around 30 total so Silverstein and Maddox  returned the fire and suppressed the batteries. Aircraft from USS Valley Forge were also called in to provide close air support. Silverstein received 110 rounds of estimated 105 millimeter batteries though she was not damaged, Maddox received two rounds. There were no allied casualties in the action.
  USS Waxbill attacked a shore battery the following day and on April 28 Silverstein and USS Conserver received fire from Ho-do Pan-do. With South Korean small craft, the allied ships bombarded the opposing battery and laid a smokescreen while other nearby ships withdrew. Conserver received ten rounds of estimated 122-millimeter fire. On May 7, USS Waxbill was fired on by twelve rounds but apparently did not return fire and on May 10, while sweeping Wonsan Harbor, USS Merganser and USS Redhead received ten rounds of enemy fire from Kalmagak.
  Also that day, Maddox and USS Laffey attacked North Korean railroad targets, scoring many hits, two railroad cars were damaged along with two buildings. Batteries on Kalmagak fired ten rounds of 76-millimeter fire at the sweepers, the nearest one landing 100 yards from the ship. Counter fire by Maddox scored two more hits. On the next day, Maddox, Laffey, USS Herbert J. Thomas and USS Evansville, received 206 rounds of seventy-five and 155-millimeter fire and an hour-long engagement.
  North Koreans were using hidden guns which were difficult to locate but were believed to have been fired from Han-do Pan-do, Hapchin-ni and Kalamagak. Return fire destroyed three enemy gun positions and Herbert J. Thomas was hit once, causing little damage and no casualties. On May 17, TG-95.2 reported that an interrogation of seven prisoners, captured off Ho-do Pan-do the day before, revealed that the enemy were planning an attack on Yodo in the near future. Troops were being concentrated in two locations on He-do Pan-do and were going to use about eighty fishing sampans for transport. Ten days later on May 27, shore batteries at Wonsan fought against USS Cabildo and Ozbourn. In a typical duel the American ships bombarded the coast and were not damaged, the day after USS Ozbourn acce
caption: USS George K. MacKenzie
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