USS Capelin

History
United States
Name	Capelin
Builder	Portsmouth Naval Shipyard, Kittery, Maine[1]
Laid down	14 September 1942[1]
Launched	20 January 1943[1]
Commissioned	4 June 1943[1]
Fate	Missing north of Sulawesi after 2 December 1943[2]
General characteristics
Class and type	Balao-class diesel-electric submarine[2]
Displacement	1,526 tons (1550 t) surfaced[2] 2,414 tons (2453 t) submerged[2]
Length	311 ft 9 in (95.02 m)[2]
Beam	27 ft 3 in (8.31 m)[2]
Draft	16 ft 10 in (5.13 m) maximum[2]
Propulsion	4 × General Motors Model 16-248 V16 Diesel engines driving electric generators[3][4] 2 × 126-cell Sargo batteries[5] 4 × high-speed General Electric electric motors with reduction gears[3] two propellers [3] 5,400 shp (4.0 MW) surfaced[3] 2,740 shp (2.0 MW) submerged[3]
Speed	20.25 knots (37 km/h) surfaced[6] 8.75 knots (16 km/h) submerged[6]
Range	11,000 nm (20,000 km) surfaced at 10 knots (19 km/h)[6]
Endurance	48 hours at 2 knots (4 km/h) submerged[6] 75 days on patrol
Test depth	400 ft (120 m)[6]
Complement	10 officers, 70–71 enlisted[6]
Armament	10 × 21-inch (533 mm) torpedo tubes 6 forward, 4 aft 24 torpedoes 1 × 4-inch (102 mm) / 50 caliber deck gun Bofors 40 mm and Oerlikon 20 mm cannon

USS Capelin (SS-289), a Balao-class submarine, was the only ship of the United States Navy to be named for the capelin, a small fish of the smelt family. She is credited with having sunk 3,127 gross register tons of shipping on her single war patrol.

Capelin′s keel was laid down by Portsmouth Naval Shipyard at Kittery, Maine. She was launched on 20 January 1943, sponsored by Mrs. I. C. Bogart, and commissioned on 4 June 1943.

Capelin sailed from New London, Connecticut, on 3 September 1943, bound for Brisbane, Australia, and duty with Submarine Force, Southwest Pacific. Her first war patrol, conducted in the Molucca Sea, Flores Sea, and Banda Sea between 30 October and 15 November, found her sinking a 3127-ton Japanese cargo ship on 11 November off Ambon Island.

Capelin returned to Darwin, Australia, with a defective conning tower hatch mechanism, excessively noisy bow planes, and a defective radar tube. These flaws were corrected, and Capelin put out on her second war patrol 17 November 1943, in the Molucca Sea and Celebes Sea, and she was to pay particular attention to Kaoe Bay, Morotai Strait, Davao Gulf, and trade routes in the vicinity of Siaoe Island, Sangi Island, Talaud Islands and Sarangani Island. She was to leave her area at dark 6 December.

The submarine Bonefish (SS-223) reported sighting an American submarine on 2 December 1943 in the area assigned to Capelin at that time. The unidentified submarine quickly dived, probably after sighting Bonefish. Bonefish sent a message via sonar giving Commander Marshall's nickname, "Steam". The other submarine returned an acknowledgement.^[8] Following this, Capelin was never heard from again. The U.S. Navy broke radio silence on 9 December 1943 in an attempt to contact Capelin, but without success.

Japanese records studied after the war listed an attack by the minelayer Wakataka on a supposed United States submarine on 23 November 1943 off Kaoe Bay, Halmahera, Indonesia, with the Japanese ship noting the attack produced oily black water columns that contained wood and cork splinters and that later a raft was found. This is the only reported attack in the appropriate area at that time, and it occurred nine days before Bonefish's apparent contact with Capelin. Also, Japanese minefields are now known to have been placed in various positions along the north coast of Celebes (now known as Sulawesi) in Capelin's patrol area, and she may have been lost to a naval mine. Gone without a trace with the loss of her entire crew, Capelin remains on the list of ships lost without a known cause.

• 

  
  Asiatic-Pacific Campaign Medal with one battle star
• World War II Victory Medal

• List of U.S. Navy losses in World War II
• List of people who disappeared mysteriously at sea

• Kill Record: USS Capelin Archived 4 June 2023 at the Wayback Machine
• On Eternal Patrol: USS Capelin