USS S-24 in the 1920s.
History
United States
Name	USS S-24
Builder	Bethlehem Shipbuilding Corporation, Quincy, Massachusetts
Laid down	1 November 1918
Launched	27 June 1922
Sponsored by	Mrs. Herbert B. Loper
Commissioned	24 August 1923
Decommissioned	10 August 1942
Stricken	25 August 1947
Fate	Transferred to United Kingdom 10 August 1942 Returned 1944 Scuttled 25 August 1947
United Kingdom
Name	HMS P555
Acquired	10 August 1942
Commissioned	October 1942
Decommissioned	May 1944
Fate	Returned to U.S. Navy December 1944
General characteristics
Class and type	S-class submarine
Displacement	854 long tons (868 t) surfaced 1,062 long tons (1,079 t) submerged
Length	219 ft 3 in (66.83 m)
Beam	20 ft 8 in (6.30 m)
Draft	15 ft 11 in (4.85 m)
Speed	14.5 knots (16.7 mph; 26.9 km/h) surfaced 11 knots (13 mph; 20 km/h) submerged
Complement	42 officers and men
Armament	1 × 4 in (102 mm)/50 deck gun 4 × 21 inch (533 mm) torpedo tubes

USS S-24 (SS-129) was a first-group (S-1 or "Holland") S-class submarine of the United States Navy. During World War II, she also served in the Royal Navy as HMS P555.

S-24′s keel was laid down on 1 November 1918 by the Bethlehem Shipbuilding Corporation's Fore River Shipyard in Quincy, Massachusetts. She was launched on 27 June 1922, sponsored by Mrs. Herbert B. Loper, and commissioned on 24 August 1923 with Lieutenant Commander Louis E. Denfeld in command.

Operating from New London, Connecticut, in 1923 and 1924, S-24 served at Saint Thomas, United States Virgin Islands, in February 1924. She visited Trinidad from 6 to 13 March 1924, the Panama Canal area in April 1924, and Hawaii from 27 April 1924 to May 1925. She served principally at San Diego, San Pedro, and Mare Island, California, until 1930, also serving in the Panama Canal area in February and March 1926, visiting Hawaii in 1927 and 1928, serving in the Panama Canal area again in February 1929, and making two visits to Hawaii during 1929.

Departing San Diego on 1 December 1930, S-24 arrived at Pearl Harbor, Hawaii, on 12 December 1930. She operated from Pearl Harbor until 15 October 1938, when she got underway for New London, which she reached on 4 January 1939. After serving in commission in reserve with a partial crew at New London from 1 April 1939, S-24 resumed full duty with a full crew on 1 July 1940. She then operated from New London until December 1941.

After the United States entered World War II with the Japanese attack on Pearl Harbor on 7 December 1941, S-24 served in waters near the Panama Canal from late December 1941 until May 1942. Returning to New London on 21 May 1942, she decommissioned there on 10 August 1942.

On the day she was decommissioned, S-24 was transferred to the United Kingdom. In the Royal Navy, she was commissioned as HMS P555 in October 1942 and was assigned to the 7th Submarine Flotilla, a flotilla based at Holy Loch, Scotland, used for training new submarine officers and crews and for training surface warships in anti-submarine warfare. Among the officers who commanded her was Royal Naval Volunteer Reserve (RNVR) Lieutenant Edward Preston Young, making P555 the first Royal Navy submarine to be commanded by a British RNVR officer.^[1] The Royal Navy decommissioned P555 in May 1944 and returned her to the U.S. Navy in December 1944.

After her return, the U.S. Navy struck S-24 from the Navy List. She was scuttled in the English Channel off Portland Bill on 28 April 1947 for use as a sonar target.^[2] (or 25 August 1947^[3]).

 This article incorporates text from the public domain Dictionary of American Naval Fighting Ships. The entry can be found here.

50°30.87′N 2°33.43′W / 50.51450°N 2.55717°W / 50.51450; -2.55717