This is the first volume of a new collection dedicated to the evolution of techniques and materials used by special services and special forces.In October 1940, the British Intelligence Service tested the lower filtration means in occupied France by parachuting blind man Phillip Schneidau near Montigny, on the edge of the forest of Fontainebleau.The British parachute would then quickly establish itself as one of the main infiltration methods and was adopted by the Allies, including the American Operational Groups in Jedburgh, and OSS (Office of Strategic Services, the precursor of the CIA).This study will focus on parachutes Type A and X. Its successor, the PX type, is also discussed and made to better understand the differences and developments.