In WWII, the remarkable Air Transport Auxiliary force of civilian pilots freed up Royal Air Force and Fleet Air Arm pilots for the fighting by ferrying new aircraft from factories to their squadrons or from squadrons to maintenance units for repairs.

Its members, eventually numbering more than 1,300 from 28 countries, were excluded from military service because of their health, age - or sex: 168 of the pilots were women.

The ATA's unofficial motto was "anything to anywhere'. Its pilots delivered more than 300,000 aircraft of 147 types - fighters and bombers, but without armament - as far afield as Egypt, Scandinavia and Russia.

My picture imagines a newly-built Spitfire Mk IXc, its squadron code letters not yet painted on, above sunlit clouds on its way to a frontline fighter squadron.