Armadillo Aerospace‘s quad rocket vehicle showing visible banding (shock diamonds) in the exhaust plume from its propulsion system Propulsion is a means of creating force leading to movement. A propulsion system has a source of mechanical power (some type of engine or motor, muscles), and some means of using this power to generate force, such as wheel and axles, propellers, apropulsive nozzle, wings, fins or legs. Other components such as clutches, gearboxes and so forth may be needed to connect the power source to the force generating component. The term propulsion is derived from two Latin words: pro meaning before or forwards and pellere meaning to drive.   Vehicular propulsion Air propulsion Main article: Powered aircraft A turboprop-engined Tupolev Tu-95 An aircraft propulsion … Continue reading Non-Classified Earth Propulsion Systems