On 11 November 1940, Swordfish flying from achieved great success in the Battle of Taranto. The main fleet of the Italian Navy was based at Taranto in southern Italy; in light of the success of the earlier attack upon the French Navy at Mers-el-Kébir, members of the Admiralty sought another victory under similar conditions. The Royal Navy had conducted extensive preparations, with some planning having taken place as early as 1938, when war between the European powers had already seemed inevitable. Regular aerial reconnaissance missions were flown to gather intelligence on the positions of specific capital ships and Swordfish crews were intensively trained for night flying operations, as an undetected aerial attack during the night raid had been judged to be the only effective method of reasonably overcoming the defences of the well-protected harbour and to strike at the fleet anchored there.