MT Deerhound (formerly RMAS Deerhound) is a Dog-class medium berthing tugboat built for the Royal Maritime Auxiliary Service (RMAS) in 1966 by Appledore Shipbuilders, Appledore, North Devon. Both Deerhound and her sister Elkhound were designed to work with the Polaris submarines of the Royal Navy and as such they are fendered all the way down the stem and part way along the keel to prevent damage to the submarines hull under water. In July 1983, during Deerhound's time with the RMAS, she met the submarine HMS Conqueror, returning from taking part in the Falklands War, where she sank the ARA General Belgrano. Deerhound helped her to berth at Faslane Naval Base.