The single seat Gray Goose Airways Cyclogyro N4308 c/n 1, built circa 1937, was a VTOL experiment using minimum power. Originally designed in 1923 with articulated slats, connected to a 7hp Harley-Davidson motorcycle which set the heavily-braced wings into a flapping frenzy, but before it got any serious ideas about flying its tail broke off.
All Aero 