21-in Mark V Torpedo (UK)
The 21-in R.N.T.F. Mark V Torpedo was a British torpedo developed at the Royal Navy Torpedo Factory in 1918 and 1919. The design was not finalised before the end of the war.
Development and History
In 1919, the blowing head was not completed in design, but considerable experimentation with the design had taken place in Vernon and at Loch Long. With the war over, most of those ordered were cancelled, but 800 were still expected to be delivered for use in fixed A.W. tubes in Hood, Furious, and the Renown, Courageous and Hawkins classes, as well as in triple A.W. tubes in Furious, Eagle, the Danae, Emerald class cruisers, the "W" class destroyers and flotilla leaders. It was not anticipated that "C" class light cruisers and destroyers with "close-fit tubes" would be supplied.
There were great problems getting the weapons to run correctly at 44.5 knots though they managed 29 and 35 knots nicely, and it was supposed that this is because they had too great a negative buoyancy. It was reaching 14,500 yards at 29 knots in 1919 – a figure that was dissatisfying. They resisted efforts to get them to circle or loop.
- Annual Report of the Torpedo School, 1919. pp. 12, 13.