Ships in class: 53
The Royal Navy's T class (or Triton class) of diesel-electric submarines was designed in the 1930s to replace the O, P, and R classes. Fifty-three members of the class were built just before and during the Second World War, where they played a major role in the Royal Navy's submarine operations. Four boats in service with the Royal Netherlands Navy were known as the Zwaardvisch class.
The ten-torpedo salvo was the largest ever fitted to an operational submarine. British operational planning at the time assumed international treaties would prevent unrestricted submarine warfare, and the main purpose of the submarine would be to attack enemy warships. In such a situation, a commander may only have had one chance to attack, so a large salvo was essential.