It has been suggested by sources including www.silentsf.com that this film is based upon the E. Douglas Fawcett novel Hartmann the Anarchist
Unmanned aerial vehicle | unmanned aerial vehicle | Aerial photography | List of aerial disappearances | aerial photography | aerial refueling | International Aerial Robotics Competition | Aerial warfare | aerial warfare | Aerial Lift Bridge | Aerial Ballet | U.S. Air Force's KC-135 aerial refueling tanker | First aerial circumnavigation | aerial survey | Aerial bomb | Aerial application | aerial | Unmanned Aerial Vehicle | The Anarchists | T-aerial | National Investigations Committee on Aerial Phenomena | Flying Ace Aerial Chase | Black Mask (anarchists) | Aerial work platform | Aerial view of the château d'Ainay-le-Vieil | Aerial view of Golf course ''Golfplatz Wittenbeck | Aerial view of a Golf course (''Golfplatz Wittenbeck | Aerial torpedo | aerial torpedo | Aerial survey |