in fresh water was introduced - resulting in changes to the compensating water tanks. The ability to dive in waters with a specific gravity of 1.00 to 1.30 remained for all submarines until the Second World War, after which it decreased to 1.015 to. 1.03.
The Oberon, Odin, Parthian and Rainbow Classes were designed to dive to a depth of 500 feet. The Oberons were tested to 200 feet and in the three later classes the deep diving trials were to 300 feet, although it is known that some boats went deeper. Rear-Admiral Submarines (RA(S)) laid down 300ft as the test diving depth of boats designed to withstand depth pressure at 500 feet.
It is interesting to review the policy regarding deep diving. In
