Breaking The Sound Barrier - Blog Posts

Ernst Mach, Chuck Yeager, and supersonic flight

Today is the 70th anniversary of the first supersonic flight. On 14 October 1947, Air Force Captain Charles Yeager piloted the experimental Bell X-1 plane named Glamorous Glennis and “broke the sound barrier,” reaching what scientists call “Mach 1.”

Yeager’s historic flight came thirty-one years after the death of Ernst Mach, the Austrian physicist and philosopher whose research on sound particles remained obscure until aviation capabilities began to approach the speed of sound. Mach lends his name to Mach numbers, used to describe faster-than-sound travel, and Mach angles, which measure the angle of the shock waves caused by flight. In addition to his work with sound, Mach’s rejection of Newton’s ideas on space and time influenced Albert Einstein’s theory of relativity.

Image credits: 1) Chuck Yeager next to experimental aircraft Bell X-1 Glamorous Glennis, 1940s. US Air Force, Public Domain via Wikimedia Commons. 2) Ernest Mach from the Journal of Physical Chemistry, Volume 40, 1902. H. F. Jütte. Uploaded by Armin Kübelbeck, Public Domain via Wikimedia Commons. 3) Chuck Yeager at Nellis Air Force Base on the 65th anniversary of his flight, 14 October 2012. Master Sgt. Jason Edwards, US Air Force, Public Domain via Wikimedia Commons.