An air defense after France's defeat
The Battle of Britain is usually dated, following the British official definition, from July 10 to October 31, 1940. This interval principally describes the contest for air superiority over Britain, rather than the full duration of German air attacks on the country. In his despatch written in 1941, Dowding acknowledged that the starting point was a matter of demarcation. He chose July 10 because large aircraft formations attacked a Channel convoy that day.
France's defeat gave Germany continental airfields close to Britain. The Luftwaffe under Hermann Göring sought to weaken British aerial resistance in preparation for invasion. Hugh Dowding commanded the Royal Air Force's Fighter Command, while Keith Park led No. 11 Group, responsible for southeastern England. German attacking distances had shortened, while Britain had to divide limited resources among shipping, airfields, and cities.
Radar required people and a layered command system
Coastal radar could warn of enemy aircraft before they reached the coast, but detecting a target did not automatically launch fighters. Dowding's despatch explains that radar reports first entered the headquarters filter room for checking and were then transmitted simultaneously to headquarters, groups, and sectors. Observer Corps reports of aircraft inland went first through observer centers to sectors and groups, then upward to headquarters. The two information streams ran in different directions.
Headquarters identified incoming targets and coordinated group boundaries. Groups decided which sectors to employ and how much strength to commit; sectors assigned particular squadrons and directed interceptions. This division of labor meant Hurricanes and Spitfires did not have to remain continuously on patrol awaiting the enemy. Radar nevertheless had low-altitude blind spots, while observers faced difficulties with clouds, darkness, and high-flying targets. Radios, telephone lines, and plotting personnel were equally important in turning warning into effective action.
From Channel convoys to the airfield network
The fighting initially focused on Channel convoys, ports, and the southern coast. In August, attacks increasingly targeted radar stations, airfields, and aircraft factories. Park's report submitted on September 12 described late August and early September as a critical period for his area: forward airfields and sector stations were bombed, exposing vulnerabilities in landing grounds, communications lines, and operations rooms.
At one point Biggin Hill could control only one squadron, leaving others to neighboring sectors. Its emergency operations room was also constrained by limited space and too few telephones. Personnel repaired runways, restored lines, and moved facilities day and night, preventing the destruction of some buildings from bringing operations to a complete halt. An airfield's continued operation depended on repair capacity and cooperation with adjacent units, not simply the number of aircraft remaining on a particular day.
Replacing pilots and sustaining ground work
Increased aircraft production could not replenish trained pilots at the same speed. Continuous combat depleted personnel and experienced formation leaders, requiring Fighter Command to rotate squadrons and arrange training. Polish and Czechoslovak pilots joined British squadrons as well as forming units of their own. No. 303 Polish Squadron and No. 310 Czechoslovak Squadron became part of the fighting force, while language and coordination problems still had to be addressed through training.
Canadian personnel likewise served in different organizational forms: RAF No. 242 Squadron must not be confused with Canada's No. 1 Squadron, which entered combat later. Ground service also involved many roles. The Air Ministry's history of the Women's Auxiliary Air Force records members undertaking plotting, telephone, and teleprinter work early in the war. Maintenance, communications, and information processing jointly sustained interception; defense was not the work of fighter pilots alone.
London raids and the debate over formations
On September 7, large-scale German daylight attacks shifted to London, damaging Thames docks, warehouses, and residential districts, followed by continuing night bombing. Park's report that month judged that this shift in targets eased pressure on No. 11 Group's sector stations. This was a theater commander's assessment, not a claim that airfields were henceforth safe or that Britain had stopped suffering serious losses.
On September 15, Britain again mounted a large-scale response to German formations. Park and No. 12 Group commander Leigh-Mallory disagreed over how best to engage them. Park's area had little warning time, while Leigh-Mallory favored first assembling several squadrons into large formations. Richards's official history places the dispute within the different timing and mission constraints of their respective areas. This explains command choices better than using one air battle to prove that a particular formation method was always correct.
Invasion postponed, night warfare continued
Britain's fighter defenses were not destroyed. On September 17, Hitler postponed the Sea Lion invasion plan indefinitely; on October 12, consideration of its implementation was deferred again until the following spring. German naval war records cited by Richards mention both the continuing activity of the British air force and unfavorable weather. The landing decision involved multiple conditions and cannot be reduced to a single weapon or one day's result. Britain was consequently able to continue fighting.
Successful daylight defense did not end the cities' suffering. Nighttime tracking and interception remained inadequate, and London's docks, railways, and housing were bombed. Firefighters, rescue services, and repair crews continued keeping the city functioning. The Battle of Britain and the Blitz overlapped in time. October 31 marks a boundary in the battle's chronology, not the date on which residents' lives returned to peace.