Inshore Patrol Squadron, 1942–1943 She departed Jacksonville on 31 December for the
Navy Yard,
Washington, DC, arriving there on 4 January 1942. She sailed on 21 January and the next day entered the
Norfolk Navy Yard. On 23 January, she was placed in commission in ordinary for conversion to a patrol gunboat. She was placed in full commission 20 April and assigned to
Inshore Patrol Squadron,
5th Naval District, based at
Norfolk, Virginia. On 8 May she departed Norfolk, forming part of the
escort for a
convoy en route to
Key West, Florida. She was on continuous escort duty between New York, Norfolk, and Key West until 27 August 1942, when she steamed from New York as convoy escort for
Guantanamo Bay,
Cuba, returning as escort for another convoy 12 September. She made two more convoy escort voyages to Guantanamo Bay and back to New York between 17 September and 24 October 1942. She then resumed escort duty between New York and Key West. During one period of this duty, 24 December 1942 to 13 June 1943,
Plymouth completed eight convoy escort voyages from New York to Key West and back. On 2 March 1943,
Plymouth collided with the
submarine chaser USS SC-1024 off of
Cape Hatteras, which resulted in the sinking of the submarine chaser.
Sinking, 5 August 1943 On her last voyage,
Plymouth departed
New Jersey on 4 August 1943 as part of the escort for a convoy bound for Key West. At 21.37 hours the following evening she made underwater sound contact about 90 miles east of Elizabeth City, North Carolina. As she swung left, to bear on the target, a violent
underwater explosion occurred just abaft the
bridge. The force of the explosion rolled
Plymouth to starboard. She then took on a heavy list to
port with her entire port side forward of
amidships in flames. She sank within two minutes.
Lieutenant Ormsby M. Mitchel Jr.,
USNR, in command of
Plymouth, was thrown violently against a
bulkhead and sustained serious injuries, which later required
amputation of his left leg. Despite his own condition, he directed abandon ship operations, remaining at his post until the ship went down. Rescued from a
raft by
USCGC Calypso, Lieutenant Mitchel was awarded the
Navy Cross for extraordinary heroism. Soundman 3/Class Franklin A. McGinty was also awarded the Navy Cross and
Purple Heart posthumously. Ensign Rubin Keltch, of New York City, was also awarded the Navy Cross posthumously for his service aboard the
Plymouth. Ensign Keltch unhesitatingly risked his life to assist several survivors to safety. After making sure they were safe he went back into the engine room to save several men, but although the men came out he never did. Rescue operations were hampered by heavy seas and
sharks. Only 85 of the crew survived to be taken to Norfolk on 6 August. A Board of Investigation concluded that
Plymouth had been sunk by a torpedo fired from an enemy
submarine. The submarine was . ==Awards==