Dates: 10 July – 31 October 1940

Luftwaffe Total Strength: 4,074 available aircraft including 1,107 single-seat fighters, 357 two-seat fighters, 1,380 medium bombers, 428 dive-bombers, 569 reconnaissance and 233 coastal aircraft. The Luftwaffe air strength given is from the Quartermaster General 6th Battalion numbers for 29 June 1940.

Luftwaffe Total Losses: 1,918 aircraft | 2,662 airmen

RAF Total Strength: 1,963 available aircraft including 754 single-seat fighters, 149 two-seat fighters, 560 bombers and 500 coastal aircraft. The RAF fighter strength given is for 0900 1 July 1940, while bomber strength is for 11 July 1940.

RAF Total Losses: 1,012 aircraft | 537 airmen

Note: The aircrew and aircraft losses have come from the comprehensive account in The Battle of Britain: Then and Now by Winston G. Ramsey. RAF numbers are for Fighter Command. Luftwaffe numbers cover both fighters, bombers and other aircraft.

Image: A group of German officers, including Hermann Göring, look across the English Channel at the White Cliffs of Dover, in preparation for Operation Sealion, the invasion of Britain in 1940. One of the officers is looking through binoculars at the English coastline.

“What General Weygand called the Battle of France is over. I expect that the Battle of Britain is about to begin.”
Winston Churchill, 18 June 1940

By the end of June 1940, most of Western Europe was under Nazi occupation. Within six weeks, the German Wehrmacht (armed forces) had swept across the Low Countries and France, forcing the evacuation of the British Expeditionary Force from the port and beaches of Dunkirk. Britain now stood alone, with invasion appearing imminent. The German leader, Adolf Hitler, initially hoped the isolated country would seek peace with Germany. However, the newly appointed British Prime Minister, Winston Churchill, was determined to fight on and rallied the British people with his powerful rhetoric and steadfast leadership. As a result, Hitler ordered his armed forces to prepare for a full-scale invasion of Britain, codenamed Unternehmen Seelöwe (“Operation Sea Lion”). A key prerequisite for the invasion was the elimination of the Royal Air Force (RAF) to ensure that the German Air Force, the Luftwaffe, possessed air superiority over the English Channel and southern England. To achieve this, Hitler turned to Reichsmarschall Hermann Göring, Commander-in-Chief of the Luftwaffe. After the early triumphs in Poland and France, Göring believed that Britain could be brought to its knees by air power alone. He was confident that British fighter defences would be destroyed in a matter of days. On 1 July, three Luftflotten (air fleets) were deployed from Norway to Brittany with a strength of 2,186 serviceable aircraft, including 898 bombers, 708 single-engined fighters, and 202 twin-engined fighters.

The defence of Britain relied primarily on RAF Fighter Command, led by Air Chief Marshal Sir Hugh Dowding. At the outset of the battle, Fighter Command had 640 serviceable fighters, organised into four groups: No. 13 Group covered Scotland and northern England; No. 12 Group, the Midlands and East Anglia; No. 10 Group, the South West; and No. 11 Group, the most vital, was responsible for the South East and London. Each group was divided into sectors, with sector stations serving as operational control centres. This structure formed part of Dowding’s pioneering integrated air defence system, which provided a decisive advantage over a numerically superior enemy.

At the core of this system was a chain of radar stations along the British coast, giving early warning of approaching raids. Combined with observer reports and centralised command and control, this network allowed RAF fighters to be scrambled in time to intercept incoming formations.

On 10 July, the Luftwaffe began a series of attacks on convoy shipping in the English Channel and coastal targets. This campaign would continue for the next month and came to be known as the Kanalkampf (“Channel Battles”). The primary aim was to cut vital British overseas supply lines and lure RAF fighters into battle to weaken the air defence before the main offensive. Due to the proximity of German airfields to the coast, Fighter Command often lacked sufficient warning to block the convoy attacks. As a result, the RAF was forced to fly standing patrols, which put considerable strain on both pilots and aircraft. Eventually, the number of ship-sinkings became so great that the British Admiralty cancelled all further daylight convoys through the Channel.

The all-out assault to destroy the RAF was codenamed Unternehmen Adlerangriff (“Operation Eagle Attack”) and would begin on Adlertag (“Eagle Day”). This was originally scheduled for 10 August, but bad weather forced a postponement. On 12 August, the Luftwaffe launched preliminary raids on radar stations and coastal airfields used as forward landing grounds by RAF fighters. The damage was limited, with only one radar station temporarily put out of action.

The Luftwaffe was finally given the order to launch Adlertag on 13 August and flew 1,485 sorties against RAF airfields, ports, and aircraft factories, causing extensive damage. However, many of the airfields targeted were misidentified as Fighter Command bases due to poor intelligence, and British fighter defences remained fully operational. Approximately 15 RAF fighters were destroyed, while the Luftwaffe lost 39 aircraft. On 15 August, the Luftwaffe attempted to overwhelm Fighter Command by mounting the largest number of sorties of the campaign, with all three air fleets deployed for the first time in a coordinated effort. This became known as the “Greatest Day” after RAF fighters shot down 76 German aircraft for the loss of 35. Undeterred, the Luftwaffe continued to launch large-scale attacks against RAF airfields and radar stations, with the heaviest losses of the battle occurring on 18 August, the “Hardest Day.”

The pressure on Fighter Command increased between 24 August and 6 September, when the Luftwaffe shifted its main effort to the airfields and sector stations of No. 11 Group. This would later be known as the critical phase. The sustained attacks forced Fighter Command to take emergency measures to keep the sectors operating. Many RAF pilots were stretched to the limits of their endurance, and pilot losses began to exceed the output of the training schools. Ground crews also suffered heavy casualties, and many maintenance facilities were destroyed. Yet despite the severe strain, RAF fighters continued to inflict heavy losses on the Luftwaffe.

The battle took an unexpected turn on the night of 24/25 August, when German bombers mistakenly dropped bombs on the city of London. Believing this to be a deliberate attack, Churchill immediately ordered RAF Bomber Command to launch reprisal raids on Berlin the following night. Hitler was outraged and, on 5 September, ordered the Luftwaffe to concentrate its attacks on London and other major British cities. German intelligence believed that Fighter Command was on the verge of collapse and that an attack on the capital would draw the last remaining fighters into a decisive battle. In reality, British fighter production – under the direction of Lord Beaverbrook – had continued to rise and kept pace with losses. The shortage of trained pilots was also alleviated by transfers from other service branches and the activation of Polish, Czech, and Canadian squadrons. On 7 September, nearly 400 German bombers targeted the docks in the East End of London, killing 430 civilians and injuring 1,600. This marked the beginning of 57 consecutive nights of bombing, the opening phase of what became known as the Blitz. Initially, the British were caught off guard, but the shift in strategy gave Fighter Command a critical respite to regroup and repair its most badly damaged airfields.

On 15 September, now commemorated as Battle of Britain Day, the Luftwaffe launched its largest and most concentrated daylight assault on London, hoping to force a final, decisive confrontation. The German raids were met with a determined RAF response, and the Luftwaffe suffered its heaviest losses of the month. It became clear that Fighter Command was far from collapse and that the Luftwaffe could not achieve the air superiority required for invasion. Two days later, Hitler postponed all invasion preparations indefinitely. Although daylight air battles continued into October, the Luftwaffe shifted its primary focus to night bombing to reduce further losses.

The failure of the Luftwaffe to destroy the RAF is considered the first major German defeat of the Second World War. The defensive victory gave Britain the time and breathing space to rebuild its strength and eventually serve as the staging ground for the D-Day landings in June 1944. This in turn led to the liberation of Western Europe. The RAF airmen who stood in defence of Britain were immortalised by Winston Churchill with the words:

“Never in the field of human conflict was so much owed by so many to so few.”