William Littlewood graduated from Cornell University (Class of 1920) with a degree in mechanical engineering. He taught physics, mechanics, and machine design at Cornell, was awarded the Sibley Prize for engineering scholarship for two years, and was president of the Cornell Society of Engineers. He was an honorary fellow of the Royal Aeronautical Society of the United Kingdom, of the Canadian Aviation and Space Institute, and of the American Insitute of Aeronautics and Astronautics. He was president of the American Institute of Aeronautical Sciences, a member of the Cornell Engineering Council, and president of the Society of Automotive Engineers. He received an honorary doctor of engineering from the University of Maryland, the Flight Safety Foundation Medal, the Daniel Guggenheim Medal, and the Wright Brothers Medal. He helped to develop the DC-3, DC-4, DC-6, DC-7, Boeing 707, and Convair 990. In 1944, President Franklin D. Roosevelt named him to the National Advisory Committee for Aeronautics. He later became chairman of NASA's Research Advisory on Aircraft Operating Problems. He was elected a Cornell alumni trustee in 1955, and at the time of his death was vice chairman of the executive committee of the Board of Trustees of Cornell University.