This was an Allied programme of air operations in direct support of General Sir Bernard Montgomery’s Allied 21st Army Group in 'Neptune' (iii) and 'Overlord' (6 June 1944).
These operations were entrusted to Air Marshal Sir Arthur Coningham’s British 2nd Tactical Air Force and Lieutenant General Lewis H. Brereton’s US 9th AAF under the overall control of Air Chief Marshal Sir Trafford Leigh-Mallory, the Allied air commander-in-chief.