The Spitfire F.21 entered service with No 91 Squadron at Manston in January, despite having suffered early handling problems. The squadron began operations with modified aircraft from Ludham in March, flying armed reconnaissances and on 16 April, two aircraft strafed a midget submarine they caught on the surface and claimed it as sunk.
Spitfires also escorted Lancasters and Halifaxes on two of the last major raids of the war - daylight attacks on Heligoland and Wangerooge. One of the pilots was Bobby Oxspring who had started on Spitfires with No 66 Squadron in February 1939 and was now finishing the war as Wing Leader of No 24 Wing, still flying Spitfires.
As well as providing escort to the bombers, Spitfires were being used as dive-bombers with 250lb and 500lb bombs or, more rarely, as rocket-firing fighter-bombers. Little was seen of the Luftwaffe after New Year's Day but the flak remained intense and accurate. Targets for the Spitfires were varied, and included factories, road and railways communications and German Troop positions.
More than 3,000 F.21s had been ordered when the end of the war brought drastic cuts and only 120 were built - enough to equip four squadrons. A few were fitted with contra-rotating propellers, which eliminated skidding and made the aircraft very stable as a gun platform. This idea was later adopted for the Seafire 47.
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