At the beginning of World War I Mesudiye was ordered to anchor just south of the Dardanelles Narrows at Chanak, in Sarisiglar Bay as a floating battery to protect the minefields. Both the ship's captain, Besiktasli Arif Nebi, and several officers protested this order, but the opinions of the German naval advisors prevailed.
On 13 December 1914 the British submarine B-11 entered the Dardanelles, and torpedoed the Mesudiye from a range of 800 m (2,600 ft) exactly at noon, as the ship's crew gathered belowdecks for lunch. Lookouts saw the torpedo and B-11's periscope, and sounded the alarm, and the Mesudiye’s guns began to fire towards the point where the submarine had been sighted. The impact of the first torpedo caused the Mesudiye to heel severely. She capsized in 10 minutes, trapping most of the crew; however, as she was lying in shoal water, most of the hull was above the surface, so most of her crew were rescued by cutting through the hull. Thirty-seven men were killed in all, 10 officers and 27 men.
The Mesudiye’s guns were salvaged and mounted in a shore battery bearing her name, and later caused substantial damage to the French battleship Bouvet on 18 March 1915.
The sunken Mesudiye from Jane's War at Sea 1897-1997
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