Empire Ace was a 276 GRT coastal tug built by Cochrane & Sons, Selby. Launched on 12 Sepetmber 1942 and completed in December 1942. Sent to Malta, naval manned, where she was sunk in an air raid on 15 March 1944. Salvaged on 10 May and repaired. CD manned at Malta 1946 and in 1947 renamed Diligent. Towed to Devonport 1958. Reverted to RFA Empire Ace in 1961 based Clyde. On loan to the US Navy. Ran aground near Campbeltown on 11 November 1968 and abandoned. Refloated in June 1969 but a constructive total loss. Scrapped at Campbeltown in 1971.