During the second week of October 1943, the Eighth flew a series of maximum-effort missions. Their first targets were in the Bremen-Vegesack area on October 8th. The next day their targets were Anklam, Marienburg, Danzig and Gdynia. On October 10th they bombed Münster. The Eighth lost eighty-eight heavy bombers on these strikes. Next on Thursday, 14 October 1943 the Eighth attacked the ball bearing plant at Schweinfurt. It became the largest air battle so far between two opposing air armies, the Eighth with 229 bombers and the Luftwaffe with over 300 fighters. Their battle line extended over 800 miles and the action lasted for three hours and fourteen minutes. Only thirty-three American bombers returned without battle damage and among the 2,900 men there were 642 casualties. For the Eighth it was a loss of over 18 percent of the force. The Luftwaffe losses were also high with more than a hundred aircraft destroyed or damaged. For the Eighth, 14 October 1943 was thereafter known as Black Thursday. The costly 14 October 1943 mission against Schweinfurt caused significant damage to the ball-bearing plant. This forced Germany to recognize the threat that daylight strategic bombing presented to its capability to wage war and to geographically disperse key industries to maintain production.
Veterans remember the Mighty Eighth’s losses from 8 October to 14 October 1943 as National Eighth Air Force Week. 
Black Week: Leading up to 2nd Schweinfurt Mission
During the second week of October 1943, the Eighth flew a series of maximum-effort missions. Their first targets were in the Bremen-Vegesack area on October 8th. The next day their targets were Anklam, Marienburg, Danzig and Gdynia. On October 10th they bombed Münster. The Eighth lost eighty-eight heavy bombers on these strikes. Next on Thursday, 14 October 1943 the Eighth attacked the ball bearing plant at Schweinfurt. It became the largest air battle so far between two opposing air armies, the Eighth with 229 bombers and the Luftwaffe with over 300 fighters. Their battle line extended over 800 miles and the action lasted for three hours and fourteen minutes. Only thirty-three American bombers returned without battle damage and among the 2,900 men there were 642 casualties. For the Eighth it was a loss of over 18 percent of the force. The Luftwaffe losses were also high with more than a hundred aircraft destroyed or damaged. For the Eighth, 14 October 1943 was thereafter known as Black Thursday. The costly 14 October 1943 mission against Schweinfurt caused significant damage to the ball-bearing plant. This forced Germany to recognize the threat that daylight strategic bombing presented to its capability to wage war and to geographically disperse key industries to maintain production.
Veterans remember the Mighty Eighth’s losses from 8 October to 14 October 1943 as National Eighth Air Force Week. 