May 052014
Silent footage of the XF-88 modified as a turboprop aircraft, rather than the standard put turbojet. The prop at the nose could be disengaged and feathered, as is shown clearly here. The idea was that at the time turboprop aircraft had substantially greater range than turbojets, which drank their fuel with abandon; the blades of this propeller were designs so that the tips would actually break the sound barrier. The hope was that a fighter could be designed to be both fuel efficient and break the sound barrier, but the sound produced by the supersonic propeller was so horrifically loud and screechy that it caused physical injury to ground crew. The idea obviously was not adopted.
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