After flying with the 94th Pursuit Squadron from 1931 to 1934, Colonel McCoy was assigned to fly the Army Air Mail during the air mail crisis of 1934. With advanced degrees in Aeronautical Engineering, he later became Chief of the Propeller Laboratory at Wright Field, Dayton, Ohio, where he advanced the science of propellers and contributed many of his own propeller related patents.

Colonel McCoy helped develop the great WWII technical intelligence collection program in Europe which captured German aircraft, equipment and documents. He was the father of today's Defense Technical Information Center (DTIC), and during WWII he made advanced German research available to US and Allied Industry. After the war he directed Project PAPERCLIP which brought hundreds of Germany's best scientists and technicians to the US to help develop US aerospace industry. He helped develop the first technical intelligence means of collecting information about the Soviet air, missile and atomic weapons program. Colonel McCoy was a pioneer who brought the results of technical intelligence to the forefront.

Colonel McCoy's decorations include the Legion of Merit and the Bronze Star. He was a command pilot with 24 years of flying experience.