Jean de Chappedelaine at his desk in 1928, holding the 1/10th-scale model of the Gyraptere he built to demonstrate proof of his concept. On the desk to his right is the small box containing the 0-14 h.p. electric motor the inventor used to power the model. The power loading of the model could reach 9lb/h.p. based on static thrust.

A poor-quality but extremely rare photograph, first published in the September 15, 1928, issue of L’Air, showing de Chappedelaine operating the test rig of the Gyraptere scale model, apparently in captive flight, powered by a flexible drive from the electric motor housed in the box in front of de Chappedelaine. Surely the flexible drive would have had to be a lot longer to make the full-size machine a success!

The inlets of the blowers were reportedly connected to the upper surface slots in order to use boundary layer suction as a means of reducing drag.

Chappedelaine’s Gyraptere concept, its resemblance to an automobile emphasised by the four-wheel undercarriage. The machine consisted of two turbo blowers located on either side of a wingless stubby fuselage, the blowers ejecting air downward and aft, providing lift and propulsion - in theory.