HMS Challenger (K07)
 HMS Challenger was a unique vessel in Royal Navy service purpose built to support deep sea operations and saturation diving. Built by Scotts at Greenock the ship was launched on 19 May 1981 but not commissioned until 1984 during a time when the Royal Navy was cutting back on expenditure. The consequence was that the £80m Challenger was seen as an extravagance that the Admiralty could not afford.