SNECMA Coléoptère :

The SNECMA Coléoptère meaning “beetle” in French, was a VTOL aircraft developed by the French company SNECMA in the 1950s. It was a single-person aircraft with an annular wing designed to land vertically, therefore requiring no runway and very little space to take-off. There were several prototypes developed and tested, however the design proved to be very unstable and flying it was dangerous.
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