Operation Vigorous was a World War 2 Allied operation to deliver a supply convoy (MW-11) that sailed from Haifa and Port Said on 12 June 1942 to Malta. The convoy encountered heavy Axis air and sea opposition and returned to Alexandria on 16 June.

Operation Vigorous was a World War 2 Allied operation to deliver a supply convoy (MW-11) that sailed from Haifa and Port Said on 12 June 1942 to Malta. The convoy encountered heavy Axis air and sea opposition and returned to Alexandria on 16 June.

The total escorting force comprised eight cruisers and 26 destroyers supported by corvettes and minesweepers, and also the old battleship HMS Centurion, which, disarmed between the wars, had been refitted with anti-aircraft guns. Two British battleships had been sunk in Alexandria harbour in December 1941 (HMS Queen Elizabeth and Valiant), so no battleship was available to provide cover: Centurion simulated a commissioned battleship. Nine submarines were deployed as a screen at Taranto (four more operated west of Malta).

On the evening of 15 June, in view of the strength of enemy air attacks from the extended network of Axis airfields in North Africa, the presence of a large portion of the Italian fleet, lack of fuel caused by diversionary tactics and seriously depleted ammunition stocks, it was finally decided to abandon the operation and return to Alexandria.

None of the Vigorous ships reached Malta. One cruiser, HMS Hermione; three destroyers, HMS Airedale, Hasty and HMAS Nestor and two merchant ships had been lost in the attempt. Three cruisers, one destroyer and one corvette were damaged. British air attacks sank the Italian cruiser Trento and damaged Littorio. Nevertheless, the Italian Fleet succeeded in blocking the Allied convoy even if there was no direct contact between the surface forces. Royal Navy gunners shot down 21 of the approximately 220 attacking aircraft.

RFA support for the Convoy was provided by RFA Brown Ranger.