Clarence Leonard "Kelly" Johnson was an American systems engineer and aeronautical innovator. He is recognised for his contributions to a series of important aircraft designs, most notably the Lockheed SR-71 Blackbird. He was born on February 27, 1910 in Ishpeming, Michigan, U.S. Johnson was 13 years old when he won a prize for his first aircraft design. He worked his way through Flint Central High School and graduated in 1928, then went to Flint Junior College, now known as Mott Community College, and finally to the University of Michigan in Ann Arbor, where he received a master's degree in Aeronautical Engineering. In 1965, he received the National Medal Of Science. He died on December 21, 1990 in Los Angeles, California, United States.