'Calendar' (i) was a British and US naval delivery of 47 Supermarine Spitfire single-engined fighters to Malta (14/26 April 1942).

By April 1942 the situation of Malta had become desperate in terms of shortages of essential supplies, the depletion of the offensive forces and, more immediately, the complete inadequacy of the fighter defence force. By the middle of the month, aircraft numbers had fallen to very small numbers, and reinforcement was essential if the island was not to fall. No British carriers were available for further ferry trips: Ark Royal had been sunk, Argus was too small to embark the number of fighters which were needed, Furious was undergoing emergency repairs, and the lifts of the more modern and larger carriers were too small to accommodate the land-based Spitfire without a wing-folding capability. Prime Minister Winston Churchill appealed to the USA for assistance, and the US fleet carrier Wasp was made available by the personal intervention of President Franklin D. Roosevelt.

After landing at Hatson in the Orkney islands group all her aircraft except 20 fighters, Wasp moved to the Clyde river and there embarked 52 Spitfire Mk VB fighters and pilots of the RAF’s Nos 601 and 603 Squadrons. The aircraft were fitted with external fuel tanks to extend their range, but hasty and poor preparation meant that many of the tanks leaked badly, and in addition many of the fighters had faulty radios and guns which did not function properly.

The carrier departed the Clyde river on 14 April escorted by the battle-cruiser Renown and the destroyers Echo, Inglefield, Ithuriel, Partridge and US Lang and Madison. At dusk on 17 April the destroyers Antelope, Vidette, Westcott, Wishart and Wrestler relieved the original destroyer screen, whose ships then steamed to Gibraltar to fuel.

The original screen, as well as the light anti-aircraft cruisers Cairo and Charybdis, rejoined the main force at daylight on 19 March when the Gibraltar escort, less Vidette, returned to base to fuel.

Constituting Commodore C. S. Daniel’s Force 'W', Wasp and her escorts passed through the Strait of Gibraltar without pause to reduce the chances of detection, reached the carrier’s flying-off position some 805 miles (1300 km) to the west of Malta and there flew off 48 of the Spitfire fighters, the worst of whose faults had been remedied, from 05.30 on 20 April. Despite the absence of guides, 46 of the fighters reached the airfields of Malta, but were then caught on the ground, without fuel or ammunition, by a carefully planned Axis air attack before the just-landed fighters had been put into sheltered revetments or even been refuelled. Two of the aircraft were destroyed, six damaged and nine immobilised. Such was the intensity of the German air attacks on Malta’s air defences that by the morning of the next day only 27 of the aircraft were still serviceable, this figure falling to 17 by the evening of the same day and only six by 24 April.

Thus within a week Air Vice Marshal Sir Hugh Lloyd, commanding Malta’s air forces, had to signal London with an urgent request for more aircraft, which were delivered more successfully in 'Bowery'.

Meanwhile the naval force returned toward Gibraltar, being met en route by the destroyers Antelope, Westcott, Wishart and Wrestler during the morning of 20 April. The whole force passed through the Strait of Gibraltar, Cairo, Echo, Inglefield, Lang and Madison fuelling at Gibraltar.

Wasp flew on No. 812 Squadron of the Fleet Air Arm for passage to the UK, its personnel and stores having been embarked in Cairo. Renown, Charybdis, Antelope, Ithuriel, Partridge, Vidette, Westcott, Wishart and Wrestler detached to Gibraltar during the morning of 21 April as Wasp and her escort continued their passage to the UK.

The failure of 'Calendar] (i) had considerable repercussions. The island’s governor, Lieutenant General Sir William Dobbie, reported that Malta’s situation was now still more critical, but in London it was agreed that Dobbie should have ensured better reception conditions for the fighters (and also for an earlier convoy which had suffered severe losses after reaching harbour), and General the Lord Gort was despatched from Gibraltar, where was the governor, to replace Dobbie. The loss of the Spitfires made the subsequent 'Bowery' even more essential.