10 June 1969: The U.S. Air Force donated the first North American Aviation X-15, serial number 56-6670, to the Smithsonian Institution for display at the National Air and Space Museum. The first of three X-15A hypersonic research rocketplanes built by North American for the Air Force and the National Advisory Committee (NACA, the predecessor of NASA), 56-6670 made the first glide flight and
Butch Harbold flew the F-100 from 1958-1961 with the 23rd Tactical Fighter Squadron/36th Tactical Fighter Wing, Bitburg, Germany and from 1961-1966 with the 121st Tactical Fighter Squadron, DCANG, Andrews AFB, MD.
Harbold liked to fly his Royal Canadian Air Force basic trainer, the Super Chipmunk, at aerobatic airshows. The plane, built in 1952 was used by the military until 1964. It was modified for aerobatic maneuvers and Dr. Harbold performed “outside loops, inverted spins, “heart loops”, eight-point rolls, inverted pass, and a 45-degree inverted climb.” (1)
Dr. Harbold “is a cardiologist in Rock Hill, South Carolina. He received his medical degree from George Washington University School of Medicine and has been in practice for more than 20 years.”(2)
Source: (1) https://core.ac.uk/download/pdf/49248052.pdf
(2) https://health.usnews.com/doctors/norris-harbold-692530