The Blériot 73 was a large equal-span biplane with a fuselage suspended from the lower wing and bearing a resemblance to, and slightly larger than, the Blériot 71, with the exception of the flying-boat like fuselage, attached beneath the lower mainplane, sweeping elegantly upwards to the biplane tail unit with twin rudders.. Four 300 horsepower Hispano-Suiza 8Fb water-cooled V-8 engines were mounted as close to the centreline as possible, two on the upper wing leading edge and two on the lower wing.