High Quality Content by WIKIPEDIA articles! Leonard Michael Greene (June 8, 1918 – November 30, 2006) was an American inventor and aerodynamics engineer who held more than 200 patents, many of which are aviation-related. He is most well known for his contributions to aviation technology, including his invention, the Aircraft Stall Warning device, which warns pilots when a deadly aerodynamic stall is imminent. To build the device, Greene established the Safe Flight Instrument Corporation in 1946.