Self-glider with lift propellers, French Patent 463968 of 1913
A French patent specification filed in 1913 by Société Anonyme l'Aera, describing a glider fitted with lifting propellers, drawn for patent examiners and engineers. The plates are ink line drawings on tinted paper: numbered figures, airfoil sections, plan views of segmented rotor discs with hatched blades, wheel-and-cable rigging, and dotted airflow lines usable as technical diagram motifs.
