HALL OF FAME / inventor profile

Leonard Michael Greene
Born Jun 8 1918 - Died Nov 30 2006

Stall Warning Device for Airplanes Aircraft Stall Warning Device
Patent No. 2,478,967

Inducted 1991

Leonard Michael Greene has patented dozens of inventions in aviation technology, including the device that warns pilots when a deadly aerodynamic stall is imminent.

Invention Impact

At the time Greene invented the stall-warning device, more than half of all aviation deaths were caused by the stall/spin. A Saturday Evening Post article (Oct. 25, 1947) said of Greene's innovation, 'It may be the greatest life saver since invention of the parachute.'

Inventor Bio

Born in New York City, Greene received his B.S. and M.S. degrees from City University of New York. In 1977 he was awarded an honorary doctorate by Pace University. During World War II, Greene joined the Grumman Aircraft Corporation as an aerodynamicist and engineering test pilot. Witness to an aircraft accident caused by stall, he realized the pilot could not tell when the angle of airflow over the wing had become excessive. The stall-warning device Greene then invented brought him his first of more than 100 patents to date, 60 of which cover aviation technology. To build his invention, Greene established the Safe Flight Instrument Corporation in White Plains, New York, in 1946. Other Greene inventions added to the product line included a wind-shear warning system that warns a pilot if an aircraft enters a dangerous microburst and provides escape guidance. Today the firm supplies unique air safety and performance technology to virtually every major air carrier, the U.S. Armed Forces, and to aircraft manufacturers worldwide. Since 1974, Greene has also been president of the Institute for Socioeconomic Studies in White Plains, New York. He has written a book entitled Free Enterprise Without Poverty, and articles on socioeconomics.

© 2002 National Inventors Hall of Fame