Blériot-SPAD S.91

The Blériot-SPAD S.91 was a light-weight fighter aircraft by the French aircraft manufacturer Blériot, developed in response to a French government program for a light fighter, referred to as Jockey. It was a single-seat single-bay biplane that resembled the pursuit aircraft of Blériot's lead designer André Herbemont except for its wing profile, with a framework using a substantial amount of duralumin and other light metals, a single duralumin tube girder supporting the fuselage aft of the cockpit, and mostly fabric covering. The first prototype made its maiden flight on 23 August 1927 and was lost in an accident during flight testing. The government lost interest in the concept, though Blériot kept promoting the type, and at least one prototype ended up in the Spanish Republican Air Force in 1936. The S.91 never entered quantity production and was developed into the S.510.