| Operation Calendar | |
|---|---|
| Part of the Battle of the Mediterranean of the Second World War | |
.jpg) A Spitfire takes off from USS Wasp. | |
| Operational scope | Operational |
| Planned by | Air Ministry, Royal Air Force, Royal Navy, US Navy |
| Objective | Reinforcement of Malta with Spitfire fighters |
| Date | 14–26 April 1942 |
| Executed by |  United States United Kingdom |
| Outcome | Spitfires were shot down or damaged on the ground soon after they arrived |
| Casualties | 1 pilot failed to arrive |
Operation Calendar (14–26 April 1942) was an Anglo–American operation in the Second World War to deliver 52 Supermarine Spitfire fighter aircraft to Malta. Spitfires were necessary to challenge Axis air superiority over Malta because they had the performance that Hurricane fighters lacked. Aircraft carriers were necessary to get fighter aircraft to positions in the western Mediterranean from which they had the range to reach Malta but British aircraft carriers were busy elsewhere, under repair or too small to deliver enough Spitfires to be effective.
USS Wasp was in European waters and was loaned to the British to ferry a large number of Spitfires in one voyage. Wasp picked up the fighters in the Clyde and became part of Force W, to sail to the Strait of Gibraltar, rendezvous with ships from Force H based at Gibraltar, to make a Club Run, in which 48 of the 52 Spitfires were dispatched to Malta and 47 arrived. Massed air raids by the Luftwaffe and Regia Aeronautica led to the rapid destruction or damage to the Spitfires once at Malta. The failure of the Spitfires delivered to Malta led to Wasp making another Club Run in May (Operation Bowery).