Ordered as part of the 1917 Emergency War Programme, 10 of the class were completed between 1918 and 1919.
Designed with 6 bow torpedo tubes and for Anti U-boat duties, these boats were the forerunner of the modern Hunter Killer Submarines.
During the war, British submarines often failed in attacking U-boats as they were unable to close the range after the initial sighting.
To overcome this problem, a submarine with a high submerged speed was proposed and the R Class was born.
In order to obtain the high underwater speed required, two large electric motors and batteries used in the J class
submarines were installed. The single diesel engine installed did not have the capacity to provide both surface propulsion and
completely recharge the batteries. It took almost a full day to fully charge the batteries with no other load being taken from the diesels.
For this reason the batteries could only be fully charged whilst alongside, clearly, not the best of designs.
These boats were built very late in the war so had little chance to prove themselves. Only one boat is recorded as having fired a full 6 torpedo salvo.
This did not result in a hit.
Chatham built four of the class, all with the 8 cylinder diesel engines.
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| R Class: Information | |||
| Commissioned | 1918 to 1918 | ||
| Length (feet): | 164ft | ||
| Beam (feet): | 15ft 7" | ||
| Surface Displacement (tons): | 400 | ||
| Submerged Displacement (tons): | 500 | ||
| Speed (knots): | Surface: 9.5 Dived: 15 | ||
| Armament: | 6 x 18" Bow Tubes | ||
| Propulsion: | 1 x 480 hp Diesel Engine 1 x 1,200 hp Electric Motors Single Screw |
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| Range | 2,000 nm | ||
| Complement | 22 | ||