Сазани
"Jean Bart" was torpedoed on 21 December by the Austro-Hungarian submarine off Sazan Island. A single torpedo struck her in the wine store in the bow, blowing a hole through the compartment. The ship took on of water, but was able to reach the Greek island of Cephalonia where temporary repairs were made. She was able to steam to Malta on her own for permanent repairs that lasted from 26 December to 3 April 1915. This attack highlighted the danger of submarine attacks in the restricted waters of the Strait and forced the battleships south to patrol in the Ionian Sea. The declaration of war on Austria-Hungary by Italy on 23 May and the Italian decision to assume responsibility for naval operations in the Adriatic, allowed the French Navy to withdraw to either Malta or Bizerte, French Tunisia, to cover the Otranto Barrage. At some point during the year, "Jean Bart"s 47 mm guns were put on high-angle mountings to allow them to be used as anti-aircraft (AA) guns. They were later supplemented by a pair of Mle 1891 G guns on anti-aircraft mounts. On 27 April 1916, the French began using the port of Argostoli on the Greek island of Cephalonia as a base. Around this time many men from the battleships' crews were transferred to anti-submarine ships. At the beginning of 1917, the French began to use the Greek island of Corfu as well, but growing shortages of coal severely limited the battleships' ability to go to sea. The situation was so bad that Vice-Admiral Gabriel Darrieus wrote in 1917: The military capabilities of the , which has already been badly affected by the shortages of personnel and constant changes in the general staff, need to be maintained by frequent exercises, and although from March to June we were able to follow a normal pattern, the coal crisis is currently preventing any manoeuvres or gunnery training, even for the ships returning from repairs. The big ships have lost 50 per cent of the capability they had several months ago. In 1918, they were almost immobile, leaving Corfu only for maintenance and repairs. On 1 July, the Naval Army was reorganised with "Jean Bart", "Paris" and "Courbet" assigned to the 2nd Battle Division of the 1st Battle Squadron.