Arsenal-Delanne 10
The Arsenal-Delanne 10 was an experimental fighter aircraft of French origin. The plane had a rear cockpit and a distinctive tandem wing. Design and development. The Arsenal-Delanne 10-C2 two-seat fighter, designed by Maurice Delanne and built by the Arsenal de l'Aéronautique, was of so-called Nenadovich biplane or tandem wing configuration, the tandem-mounted wings providing a continuous slot effect and offering exceptional center of gravity range. The fighter was of all metal stressed-skin construction, which used a sandwich technique, with a smooth dural skin welded to a corrugated sheet. Pilot and  gunner sat in tandem under a single canopy at the rear of the fuselage, which was level with the rear wing, which carried twin tailplanes. This arrangement gave the gunner a clear field of fire for his planned armament of two 7.5 mm machine guns, which was to be supplemented by a 20 mm cannon firing through the propeller hub and two more machine guns in the wing. The aircraft was fitted with a retractable tailwheel undercarriage and was powered by a single Hispano-Suiza 12Ycrs 12-cylinder liquid-cooled engine. The Arsenal-Delanne 10-C2 prototype was virtually complete  at Villacoublay when German forces occupied the factory in June 1940. Work on the aircraft continued in a desultory fashion and the first flight test was made in October 1941. After completion of the initial test programme, the aircraft was ferried to Germany for further trials.