English: S1 old wind tunnel, Meudon (near Paris), France.The need to understand the aerodynamic phenomena, in as close as possible to reality, driven to achieve a large wind tunnel at atmospheric pressure, in Meudon. The S1 wind tunnel for testing of aircraft in real size was built from 1932 to 1934. Through the large dimensions of the test section, S1 can experiment had real 12 m wingspan, with the engine running and the driver on board. Until the 1970s, it is mainly aircraft (the Caravelle and the Concorde) but also cars (the 4 CV and the Beetle), trains, architectural elements, who have gone through the experimental chamber to be developed or improved (maximum speed 180 km / h). This 1933 building absorbs 7,000 m3 of reinforced concrete, 700 tons of iron, 1000 m3 of wood, and requires the establishment of 566 implementation plans (see old pictures on http://www.anciensonera.fr/?q=node/17)