Bloch MB.700

When the political situation in Europe was degradating during mid-1930s, the French Air-Ministry became aware about a possible shortage of steel or light alloys and therefore they considered the non-hazardous materials as the basis for their aircrafts. Therefore the Service Technique de l'Aeronautique (Technical Aeronautical Service) issued an order for a light-fighter on 12th January 1937 called program A23. The requirements were for a fighter made out of wood and powered by engines less powerful than conventional fighters. For the contract Arsenal, Caudron and Bloch submitted their designs.
André Herbemont, who had studied every SPAD fighter since 1918, knew specially well the way of building fighters out of wood, and he couldn't miss the oportunity of working in such project. Blériot Aeronautique, a subsidiary of SPAD, based in the city of Suresnes, had been regrouped in SNCASO with the Société des Avions Marcel Bloch based at Courbevoie and Marcel Bloch, managing director of the national company, had maintaned the independence of the design offices after grouping them under his name. Therefore it was in Suresnes where André Herbemont studied and built the prototype of the Bloch MB.700.
The prototype, which was heavily inspired by the Bloch MB.152, was made out of plywood cladding, except for the rear fuselage which was made out of metal. Double-spar wings were installed and it was there where the fuel tanks were installed (326L - 86.12 US gal) and a retractable landing gear housing inwards. It was powered by a single radial Gnome et Rhône 14M-6 which delivered 700hp of power which drove a three-bladed propeller, but the prototype never had any weapons installed. It was expected to have the same weaponry of the Bloch MB.152 which was either two 20mm HS-404 guns or two 7.5mm MAC 1934 M-39 machine-guns housed in the wings.
The prototype was moved by road to Buc (where the STA performed their tests) and flew for the first time on 19th April 1940 at the hands of Daniel Rastel. It wasn't until 13th May when it flew again, at the hands of Rastel again. During that flight, which lasted for 50 minutes, it achieved a speed of 550 km/h (341.75mph), which was remarkable, considering the power of the engine. Tests continued after the French capitulation of June 1940 and, when the Germans occupied the town of Buc, the prototype had been flown for a total of 10.25 hours of flight. The prototype was destroyed by the Germans who thought the prototype was booby-trapped.
A second prototype which included some improvements, but it was never completed. A strengthned version, named MB.720 was also projected, but it never left the drawing board.

Sources:
1. https://fr.wikipedia.org/wiki/Bloch_MB.700 (translated)
2. https://www.militaryfactory.com/aircraft/detail.asp?aircraft_id=1555
3. Salamander Books - The Complete Book of Fighters