On the morning of August 17, 1943, a clear and sunny day with superb visibility, the 100th Bombardment Group of the USAAF's 8th Air Force, 4th Air Division took off from the United Kingdom to attack the Messerschmitt aircraft works in Regensburg, Germany. They were commanded by one of the more driven officers in the American air force, a fast-rising colonel named Curtis LeMay. This was a much more dangerous mission than any that the pilots in the unit had tried before. Raids by the 8th Air Force had previously been aimed mostly at German U-boat facilities on the coast, many in France – raids for which they could receive fighter escort for their entire time in the air.

In this raid, however, the twenty-one B-17s of the 100th Bombardment Group were placed “lowest and last,” flying at 17,000 feet at the absolute end of the 4th Air Division's bomber stream as it headed deep into Germany. Regensburg was located in southeast Germany, approximately halfway between Nuremberg and Munich. Until the 100th reached the skies over Holland, they met no opposition. Finally, at 10.17 in the morning, when the B-17s reached the Dutch town of Woensdrecht, they encountered German flak. Ten minutes later, whilst nearing the German border, the first Luftwaffe fighters appeared, two FW-190s, which attacked the unit from straight ahead.