HMS J6 was a First World War J-class submarine built for the Royal Navy by HM Dockyard at Devonport in Plymouth. Commissioned in 1916 she was sunk in a friendly fire incident by the Q-ship Cymric in October 1918.
Under her first commanding officer, Max Horton, J6 was launched on 9 September 1915 and commissioned on 25 January 1916. She and the other Js were members of the 11th Submarine Flotilla. She served in the North Sea chiefly in operations against German destroyers and U-boats. The closest she got to sinking the enemy was firing a torpedo at U-61 , but it missed its target.
On 1 December 1917 Horton was replaced as commanding officer of J6 by Lieutenant Commander Geoffrey Warburton. In April 1918, Warburton spotted the German High Seas Fleet which had put to sea in an attempt to hunt down an Allied convoy. Warburton did not identify the fleet as German and did not report his sighting to the Admiralty, had he done so it is possible that another full scale naval battle may have occurred.
HMS or hms may refer to:
HMS M30 was a Royal Navy M29-class monitor of the First World War.
The availability of ten 6 inch Mk XII guns from the Queen Elizabeth-class battleships in 1915 prompted the Admiralty to order five scaled down versions of the M15-class monitors, which had been designed to utilise 9.2 inch guns. HMS M30 and her sisters were ordered from Harland & Wolff, Belfast in March 1915. Launched on 23 June 1915, she was completed in July 1915.
Upon completion, HMS M30 was sent to the Mediterranean. Whilst enforcing the Allied blockade in the Gulf of Smyrna, HMS M30 came under fire from the Austro-Hungarian howitzer battery 36 supporting the Turkish, and was sunk on 14 May 1916.