In 1924, George McDonald also established a new world’s speed record for 1,000 kilometers in a Loeing Air Yacht. In 1924, he equaled the world’s endurance and long distance seaplane record in the Douglas World Cruiser, Boston II. In January 1929, he participated in a long flight from Wright Field, Dayton, Ohio, to France Field, Panama Canal Zone, in a tri-motored Fokker Transport being accompanied by First Lieutenant Dwight J. Canfield. This long flight marked the first attempt of the Army Air Corps to ferry an airplane from the United States to a foreign possession. The flight involved a total distance of approximately 2,900 miles. After serving in the Army Air Forces in World War II, he transferred to the U.S. Air Force when it became a separate branch of service in 1947. He retired in 1950 as a U.S. Air Force Major General.