The story of a Flying Fortress is a 1944 documentary film which provides an account of the final mission of the crew of the Memphis Belle, a Boeing B-17 Flying Fortress. In May 1943 it became the third U.S. Army Air Forces heavy bomber to complete 25 missions over Europe, but the first to return to the United States.

The dramatic 16 mm color film of actual battles was made by three cinematographers, including First Lieutenant Harold J. Tannenbaum. Tannenbaum, a veteran of World War I, was killed in action during the filming when the bomber he was in was shot down over France on April 16, 1943.

The film was directed by Major William Wyler, narrated by Eugene Kern, and had scenes at its station, RAF Bassingbourn, photographed by Hollywood cinematographer Captain William H. Clothier. It was made under the auspices of the First Motion Picture Unit, part of the United States Army Air Forces. The film actually depicted the next to last mission of the crew (see below) on May 15, 1943, and was made as a morale-building inspiration for the Home Front by showing the everyday courage of the men who manned these bombers.