To reduce the threat posed by the Italian fleet, which was based in the port of Taranto, to convoys sailing to Malta, Admiral Cunningham organised an attack code-named Operation Judgement. Fairey Swordfish torpedo bombers from HMS Illustrious attacked the Italian fleet on 11 November 1940 while it was still at anchor. This was the first time that an attack such as this had been attempted and it was studied by Japanese naval officers in preparation for the later attack on Pearl Harbor.