Did you know…
Why is it called the Luftwaffe's "Black Thursday"?
Short answer
Because of 15 August 1940, when the Luftwaffe flew the greatest number of sorties of the Battle of Britain and Luftflotte 5 attacked northern England. Of the 115 bombers and 35 fighters sent, 16 bombers and 7 fighters were destroyed. It was another major RAF victory, and within the Luftwaffe the day became known as "Black Thursday."

The day of most sorties
On 15 August 1940 the Luftwaffe flew the greatest number of sorties of the entire Battle of Britain, with Luftflotte 5 tasked with attacking northern England. Northeastern England was attacked by 65 Heinkel He 111s escorted by 34 Messerschmitt Bf 110s, while the RAF base at Driffield was hit at midday by 50 unescorted Junkers Ju 88s.
A miscalculation
The formations arriving from Denmark and Norway believed Fighter Command's strength was concentrated in the south and met unexpectedly strong resistance. Inadequately escorted by the Bf 110s, the bombers were shot down in large numbers. Of the 115 bombers and 35 fighters sent, 16 bombers and 7 fighters were destroyed. The day included a disaster for the Luftwaffe in which Restemeyer, five more Bf 110s and eight Heinkels were shot down.
"Black Thursday"
The day was another major RAF victory and became known within the Luftwaffe as "Black Thursday." By this point the Luftwaffe's accumulated attrition had become overwhelming. As a result of these losses, Luftflotte 5 did not appear in strength again for the rest of the campaign.
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