Operation Substance

Operation Substance was a British naval operation in July 1941 during the Second World War to escort a convoy from Gibraltar to Malta.

The convoy was escorted by six destroyers and covered by aircraft carrier HMS Ark Royal, the battlecruiser HMS Renown and the battleship HMS Nelson along with cruisers and destroyers.

On 23 July, south of Sardinia, there were sustained Italian air attacks which resulted in one cruiser damaged and one destroyer sunk. The 11,000 tn troop transport Sydney Star was torpedoed by an Italian MAS boat and crippled, but the destroyer HMAS Nestor assisted her safe arrival to harbour. Eventually, all the merchant ships reached Malta and an Italian raid to sink them in Grand Harbour failed.

Fairey Fulmar fighters of the RN Fleet Air Arm and RN AA gunners shot down at least 12 Axis aircraft, while six Fulmars were lost.