The Hardest Day

The Hardest Day
Part of the Battle of Britain
A Dornier Do 17Z of 9 Staffel (Squadron), Kampfgeschwader 76 (Bomber Wing 76). The bomber was shot down by Hawker Hurricane fighter aircraft of No. 111 Squadron RAF. It crash landed near RAF Biggin Hill, 18 August 1940,
Date 18 August 1940 Location Southern England and English Channel
Belligerents
United Kingdom	Germany
Commanders and leaders
Hugh Dowding Keith Park T. Leigh-Mallory	Hermann Göring Albert Kesselring Hugo Sperrle
Casualties and losses
27[1]–34 fighters destroyed[2] 39 fighters damaged[2] 29 aircraft destroyed (ground)[2] including eight fighters[3] 23 aircraft damaged (ground)[2] 10 killed[4] 8 lightly wounded[4] 11 severely wounded[4]	69[2]–71[1] aircraft destroyed 31 aircraft damaged[2] 94 killed[5] 40 captured[5] 25 wounded[5]

The Hardest Day^[2] was a Second World War air battle fought on 18 August 1940 during the Battle of Britain between the German Luftwaffe and British Royal Air Force (RAF). On that day, the Luftwaffe made an all-out effort to destroy RAF Fighter Command. The air battles that took place on that day were amongst the largest aerial engagements in history to that time. Both sides suffered heavy losses. In the air, the British shot down twice as many Luftwaffe aircraft as they lost.^[2] However, many RAF aircraft were destroyed on the ground, equalising the total losses of both sides. Further large and costly aerial battles took place after 18 August, but both sides lost more aircraft combined on this day than at any other point during the campaign, including 15 September, the Battle of Britain Day, generally considered the climax of the fighting. For this reason, Sunday 18 August 1940 became known as "the Hardest Day" in Britain.

By June 1940, the Allies had been defeated in Western Europe and Scandinavia. After Britain rejected peace overtures, Adolf Hitler issued Directive No. 16, ordering the invasion of the United Kingdom.^[6] The invasion of the United Kingdom was codenamed Operation Sea Lion (Unternehmen Seelöwe). However, before this could be carried out, air supremacy or air superiority was required to prevent the RAF from attacking the invasion fleet or providing protection for any attempt by the Royal Navy's Home Fleet to intercept a landing by sea. Hitler ordered the Luftwaffe's commander-in-chief, Reichsmarschall Hermann Göring, and the Oberkommando der Luftwaffe (High Command of the Air Force) to prepare for this task.

The primary target was RAF Fighter Command. In July 1940, the Luftwaffe began military operations to destroy the RAF. Throughout July and early August, the Germans targeted convoys in the English Channel and occasionally RAF airfields. On 13 August, a major German effort, known as Adlertag (Eagle Day), was made against RAF airfields, but failed. The failure did not deter the Germans from persisting with air raids against the RAF or its infrastructure. Five days later came the Hardest Day.