Original photo caption:

Boeing B-17 Flying Fortress levels off for a run over target. Photo shows the chin turret with .50 caliber (12.7 mm) machine guns featured in later models. The B-17 weighed about 60,000 lb (27,216 kg), carried a bomb load of 6,000 lb (2,722 kg), at a speed of approximately 300 mph (483 kmh).