HMS Thetis (N25)

Name: HMS Thetis (N25)
Address: IT

1938 shipsBritish T-class submarines of the Royal NavyBritish submarine accidentsCommons category link is locally definedLost submarines of the United Kingdom ... and 9 more

Maritime incidents in 1939Maritime incidents in March 1943Military history of MerseysideShips built on the River MerseySubmarines sunk by Italian warshipsUse British English from March 2017Warships lost in combat with all handsWorld War II shipwrecks in the Mediterranean SeaWorld War II submarines of the United Kingdom

HMS Thetis (N25) was a Group 1 T-class submarine of the Royal Navy which sank during sea trials in Liverpool Bay, England on 1 June 1939. After being salvaged and repaired, the boat was recommissioned as HMS Thunderbolt in 1940. It served during the Second World War until being lost with all hands in the Mediterranean on 14 March 1943.The Thetis accident happened after the inner hatch on a torpedo tube was opened while the outer hatch to the sea was also open. Four men successfully used the sub's one-man escape chamber before a fifth panicked and jammed it. A total of 99 men died as a result. The sinking led to the redesign of all torpedo tubes on British and Australian submarines. A latch, known as the "Thetis clip", was added to the inner torpedo tube door so it could be fractionally opened to check the tube was not open to the sea before being fully opened.

Excerpt from the Wikipedia article HMS Thetis (N25) (License: CC BY-SA 3.0, Authors, Images).