Harnessing the Sky is one of the best untold stories in 100 years of naval aviation. This biography fills an important void in the history of flight test and explores the legacy of the man who has been called “the godfather of current naval aviation.”Vice Admiral Frederick M. Trapnell’s calculated courage advanced the frontiers of Navy test flying more than any other aviator during one of the most perilous and thrilling periods of aviation history. “Trap” entered the Navy at a time when flight testing was still in its infancy- when test pilots were more likely to be stunt men than engineers; when airplanes served an ancillary and undeveloped role in the fleet; when the airplane had not yet come into its own as a weapon of war. His vision and leadership shaped the evolution of naval aviation through its formative years and beyond. When the threat of war in 1940 raised an alarm over the Navy’s deficiency in aircraft—especially fighters—Trap was brought in as head of the Flight Test Section to evaluate and direct the development of all new Navy airplanes. Trap expedited the evolution of two superb fighters that came to dominate the air war against Japan – the Corsair and Hellcat—by dramatically shortening test and development cycles for new prototypes. This remarkable feat was repeated after World War II when Trap returned as Commander of the Naval Air Test Center to lead the Navy through the challenges of transitioning to jets. Recognized for defining the operating requirements for carrier-based jet propelled aircraft, Trap personally conducted the preliminary tests of the Navy’s first generation jets. Over the course of two decades (1930-1950), Trap tested virtually every naval aircraft prototype and became the first U.S. Navy pilot to fly a jet. He pioneered the philosophy and perfected many of the methods of the engineering test pilot, demanding aircraft that pushed the performance envelope up to the limits of safety in all flight regimes. He insisted on comprehensive testing of each airplane with all of its equipment in all missions, conditions and manoeuvres it would face in wartime fleet operations. These innovations advanced the tactical capability of naval air power that have kept it at the forefront of modern aviation and stand as an enduring legacy to the man who is regarded as the foremost test pilot in a century of naval aviation.