USS Casco (AVP-12)

The third USS Casco (AVP-12) was a United States Navy Barnegat-class small seaplane tender in commission from 1943 to 1947.

Construction and commissioning
Casco was laid down on 30 May 1941 at Puget Sound Navy Yard in Bremerton, Washington. She was launched on 15 November 1941, sponsored by Mrs. W. J. Giles, and commissioned on 27 December 1941 with Commander T. S. Combs in command.

North Pacific operations
After a period patrolling and caring for seaplanes off the coast of the Pacific Northwest, Casco arrived at Sitka, Alaska, on 5 May 1942 for duty surveying Aleutian waters, laying moorings for seaplanes, and providing seaplane tender services. Based at Cold Bay, she operated at Dutch Harbor, Chernofski Harbor, Kodiak, and Nazan Bay.

Torpedoed while at anchor
While lying at anchor in Nazan Bay on 30 August 1942, Casco was torpedoed by the Japanese submarine RO-61. The resulting explosion killed five of her men and wounded 20, but prompt and clearheaded action brought flooding to a halt and got the ship underway so that she could be beached and later salvaged. Casco was refloated on 12 September 1942, and, after emergency repairs at Dutch Harbor and Kodiak, she received a thorough overhaul at Puget Sound Navy Yard.

Continued North Pacific operations
Casco returned to duty in the Aleutian Islands in March 1943, operating at Constantine Harbor, Amchitka, as tender to Fleet Air Wing Four (FAW-4). In May 1943 she moved to Attu, to care for the seaplanes conducting antisubmarine patrol and search missions in support of the United States Army's invasion of Attu, guarding against further Japanese reinforcement or penetration of the Aleutians. Casco's service in these waters where weather was often as formidable an enemy as the Japanese ended in November 1943, when she left for overhaul at Puget Sound Navy Yard.

Central Pacific operations
Casco arrived in the Marshall Islands in February 1944 to tend seaplanes of patrol squadrons at Majuro and Kwajalein during the American occupation of those atolls, and later at Eniwetok until September 1944. Temporarily assigned to carry cargo for the buildup for the invasion of the Philippine Islands, she shuttled between Saipan, Ulithi Atoll, and the Palau Islands until November 1944, then returned to seaplane tender duty, in the Palaus until January 1945, and at Ulithi until April 1945. After overhaul at Saipan, she arrived in Kerama Retto on 25 April 1945 to care not only for seaplanes, but also for a motor torpedo boat squadron, all engaged in the American invasion and occupation of Okinawa.

Casco returning to the United States West Coast in July 1945 for upkeep, and was there when hostilities with Japan ceased and World War II came to an end on 15 August 1945.

Honors and awards
Casco received three battle stars for World War II service.

Post-World War II U.S. Navy service
Her upkeep completed in September 1945, Casco returned to the Philippines in October 1945. Departing for the United States in April 1946, she then briefly assumed training duties at Galveston, Texas.

Decommissioning
Casco was decommissioned on 10 April 1947 and laid up in the Atlantic Reserve Fleet at Orange, Texas.

United States Coast Guard service
The U.S. Navy loaned Casco to the United States Coast Guard on 19 April 1949. The Coast Guard commissioned her as USCGC Casco (WAVP-370) the same day, and redesignated her WHEC-370 in 1966. During her Coast Guard career, her primary duty was to patrol ocean stations in the North Atlantic Ocean, providing weather reporting services and engaging in search-and-rescue and law-enforcement operations.

Final disposition
The Coast Guard returned Casco to the U.S. Navy in March 1969, and she was struck from the Naval Vessel Register. She was sunk as a target in the North Atlantic at latitude 36°40' North, longitude 24°16' West on 15 May 1969. Torpedoed twice, she sank at 16:33 hours, less than five minutes after the second torpedo struck her on her starboard side.