Three-quarter left front view from below of a formation of Boeing B-17F Flying Fortresses of the Eighth Air Force, 390th Bomb Group (309BG), in flight somewhere over Europe; contrails (vapor trails) made by their escort fighters curve through the sky above the formation.  Wing of photographer's B-17 visible in foreground.  Circa December 1943.
Sgt. Stanley M. Smith/United States Army Air Force
1943-09-27<sup id="cite_ref-Turner_1-0" class="reference"><a href="#cite_note-Turner-1">[1]</a></sup>
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