On October 14, 1947, U.S. Air Force Captain Charles E. “Chuck” Yeager became the first human to fly at a supersonic level in his Bell X-1, named “Glamorous Glennis” after his wife. Rogers Dry Lake, Edwards Air Force Base, formerly Muroc Air Force Base, was the setting over the Mojave Desert.
The experimental aircraft Bell X-1, built to fly faster than the speed of sound, eventually hit 700 mph and an altitude of 43,000 feet. The X-1, unlike the other aircraft so far, was launched into the air from the bomb bay of the Boeing B-29 bomber; from there, its powerful XLR-11 rocket engine sent it to its test altitude. Previous attempts at the sound barrier had experienced a juddering aerodynamic drag, but for this, its ninth powered flight, the engineers had altered the adjustable stabilizer of the aircraft so Yeager could minutely adjust the angle of attack and thereby smooth out the flow, to retain control as the aircraft approached the speed of sound.
As Yeager penetrated the sound threshold, a sonic boom echoed through the Mojave Desert in what would represent one of aviation’s milestone moments. After 20 seconds of the powered flight, the man shut off the engine, gliding to safety down to the lakebed in just 14 minutes from release to landing.
The Bell X-1 flew 78 times to as high as Mach 1.45 and 71,900 feet, providing invaluable data on both transonic and supersonic flight. Such information was important in the development of the next generation of high-performance combat aircraft during the early Cold War years, such as the North American F-100, America’s first supersonic fighter.
The mission was entrusted to Captain Yeager, a World War II ace with 11 victories, for not only was he an extremely good pilot but also he knew everything about the inner mechanics of aircraft. His ability to translate very subjective experiences of flights into cold technical data was invaluable to engineers who monitored the flights. As Yeager reflected, “The real barrier wasn’t in the sky but in our knowledge and experience of supersonic flight.”
The design of the X-1, with its extremely thin but strong wings and the fuselage shaped like a .50 caliber bullet, was one of the factors in defeating aerodynamic forces at supersonic speeds. These proved supersonic flight was not an impossibility, thus opening new vistas for both military and civilian flying.
The Bell X-1 “Glamorous Glennis” hangs at the Smithsonian’s Air and Space Museum as a testimonial arch between atmospheric flight and space exploration. The legacies of the X-1 program go on today and remain very relevant in current aeronautical research to ensure that the lessons learned from those early supersonic flights are still remembered for generations into the future.