George William Lewis was born on March 10, 1882 in Ithaca, New York, United States, the son of William Henry Lewis, a machinist, and Edith (Sweetland) Lewis. His father was a native of Geneva, New York; his mother of England. Early in Lewis' childhood the family moved to Scranton, Pennsylvania.
He completed high school at Scranton, Pennsylvania. He attended Cornell University at Ithaca, from which he received the degrees of mechanical engineer in 1908 and master of mechanical engineering in 1910. He then joined the engineering faculty at Swarthmore College.
In 1917 Lewis became engineer-in-charge of Clarke-Thompson Research in Philadelphia. Lewis' connection with the National Advisory Committee for Aeronautics began in 1917 when the committee accepted a proposal he had submitted to conduct research on the internal combustion engine. Two years later he was asked to become the committee's executive officer and to take charge of its modest research facility at Langley Field in Virginia. In 1924 he was named director of aeronautical research, a title that suitably described his responsibilities. He was to hold the post for nearly a quarter of a century.
Congress had founded the N. A. C. A. in 1915 in an attempt to bring the United States abreast of European aircraft development, for despite the pioneering work of Wilbur and Orville Wright, the United States had fallen far behind France, Germany, and England in aeronautical research and development by the outbreak of World War I. The committee members--scientists, engineers, aircraft manufacturers; representatives of government agencies and the military--guided policy as a sort of board of directors, with Lewis as the active executive. One of their early decisions was to expend the modest research funds available during the interwar years upon aerodynamics rather than on power-plant and structures research, for Lewis believed that the full potentialities of the airplane could not be realized without a thorough understanding of the aerodynamic problems of flight. Thus Lewis presided over the design, construction, and use of some of the world's outstanding wind tunnels. Existing tunnels, such as the one Lewis inherited at Langley in 1919, was capable of simulating only low-speed flight. N. A. C. A. and Lewis constructed in 1921 a variable-density wind tunnel which, through the use of highly compressed air, made it possible to simulate with models the flight of full-size airplanes at normal speeds.
Another major tunnel introduced during his administration was a turbulence-free one with which N. A. C. A. scientists carried on vital research on wing drag. Earlier studies of this phenomenon had been frustrated by tunnel turbulence not encountered in free air. With free air conditions simulated, it was possible to study various wing curvatures and determine the shape that would produce the maximum laminar flow and thus the minimum drag. The new wing, first applied to the army's Mustang fighter of World War II, gave that plane an unusually high speed in relation to engine power. Eventually seventeen wind tunnels were in operation at Langley Field alone, including those for fullscale, free-flight, and high-speed tests, as well as the study of wind gusts and ice formation. The wind-tunnel findings were verified by actual flight tests. From this research came other notable results, among them the introduction, in the late 1920's, of cowling to cover the exposed cylinders of air-cooled engines. In the 1930's the fairing of engine nacelles of multiengine planes into the wings began, and later the retractable landing gear was introduced. These streamlining features of design contributed to higher landing speeds, which in turn led to the tricycle landing gear and wing flaps for braking--also introduced by researchers working under Lewis' direction.
After an inspection trip to European aeronautical research centers in 1939, Lewis urged N. A. C. A. and Congress to appropriate funds for a new facility that would stress propulsion research. Located in Cleveland, Ohio (and named, after his death, the Lewis Flight Propulsion Laboratory), it was completed in 1942. Lewis himself helped plan and design the facility, as he did the Ames Aeronautical Laboratory, named for former N. A. C. A. chairman Joseph S. Ames, which opened in 1944 at Moffett Field in California. By this time Lewis was directing a staff of some 6, 000 researchers, most of whom he had recruited and trained himself.
Friendly and well liked, Lewis was adept at winning the confidence and support of the leaders of the military services, a relationship that was of critical importance to both N. A. C. A. and the armed forces. He also represented N. A. C. A. before congressional committees, where he proved a lucid and convincing advocate of research appropriations. Reluctant to delegate responsibility, Lewis made frequent visits to research facilities, military flying fields, and industrial factories to keep in direct contact with his research teams and with new developments in aviation. During World War II he drove himself unusually hard, and in 1945 he developed heart trouble. When his condition grew no better, he was relieved as director of research in 1947 and became a consultant to N. A. C. A.
Personally modest, Lewis was notable for attributing the results and reports of N. A. C. A. research to his most immediately concerned subordinates. As a result, his full professional character does not emerge from his writings or from inventions or discoveries credited to him. Nonetheless, his work was significantly recognized. He died of a coronary thrombosis at his summer home in Lake Winola, Pennsylvania, near Scranton, at the age of sixty-six. His remains were cremated.
During his time as director, the NACA made many advances in aeronautics including the NACA engine cowling, retractable landing gear, and streamlining studies. He received the Daniel Guggenheim Medal in 1936 for "outstanding success in . .. aeronautical research. " In 1948 he was awarded the Presidential Medal for Merit and was made an honorary officer of the British Empire.
He was elected to the National Academy of Sciences in 1945.
Lewis married Myrtle Harvey in Scranton, Pennsylvania, on September 9, 1908. They had six children: Alfred William, Harvey Sweetland, Myrtle Norlaine, George William, Leigh Kneeland, and Armin Kessler.
