[5][6] The air campaign, carried out by the bombers of the RAF and USAAF crippled the German rail networks in France and played a crucial role in disrupting German logistics and reinforcements to the invasion area.

[7] Air Officer Commanding (AOC) RAF Bomber Command Marshal Arthur Harris did not want to divert his bomber force away from their strategic campaign against German industry (known to the Germans as the Defence of the Reich campaign).

[8] On 6 March 1944, Charles Portal ordered attacks on the marshalling yards at Trappes, Aulnoye, Le Mans, Amiens, Lougeau, Courtrai and Laon.

Control of all air operations was transferred to Eisenhower on 14 April at noon.

A German Air Ministry (RLM) report of 13 June 1944 stated: "The raids...have caused the breakdown of all main lines; the coast defences have been cut off from the supply bases in the interior...producing a situation which threatens to have serious consequences" and that although "transportation of essential supplies for the civilian population have been completely...large scale strategic movement of German troops by rail is practically impossible at the present time and must remain so while attacks are maintained at their present intensity".