Dieselpunk enthusiasts may be familiar with conspiracies of Nazi flying discs. There’s actually at least a core of truth to this: German engineers did work on advanced aviation projects in which the Nazi leadership and SS took a particular interest in the final years and months of the war, hoping to stave off their defeat. The Americans, too, were interested, once the war was over. Thousands of German scientists were brought to the United States under Operation Paperclip and put to work on aircraft and missile designs.
The Discovery Channel’s 2008 documentary “Nazi UFO Conspiracy” looks into this history and the connection with UFO sightings and “black projects” of the United States military.