HMS Taurean

The HMS Taurean was a Royal Navy Trafalgar Class submarine. After hacking into the UNIT computer systems, Mickey Smith discovered it was ten miles off the coast of Plymouth. It was armed with a Sub-Harpoon UGM-84A missile, which the Ninth Doctor used to destroy 10 Downing Street and the family Slitheen members still inside. (DW: World War Three)