Production. B-17 heavy bomber. Two of the four mighty engines of a new B-17F (Flying Fortress) bomber loom up against a background of completed planes as another warship of the air awaits it flight tests at Boeing's Seattle plant. The Flying Fortress has performed with great credit in the South Pacific, over Germany and elsewhere. It is a four-engine heavy bomber capable of flying at high altitudes. Sourced from the Library of Congress.
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