Legendary test pilot Chuck Yeager – the first man to break the sound barrier and live to tell the story – died Monday in Los Angeles. The retired Air Force Brigadier General was 97 years old.
Sure October 14, 1947, Yeager climbed inside the neon orange Bell X-1 using a 10 inch broomstick. The pilot, already legendary after a series of aerial fights in WWII, had broken a few ribs the night before on a horseback ride after the living room with his wife – he needed the stick to close the door to the cockpit behind him.
At 23,000 feet, the bullet-shaped experimental aircraft, powered by a four-chamber rocket engine, fell from the bomb bay of a B-29 Superfortress. Yeager had been flying the X-1 for a few months, with the goal of pushing flight to higher speeds. But a new innovation, courtesy of the US Air Force, gave him confidence that it was time to try his luck again. A fully-flying horizontal tail, also known as a stabilizer, allowed the pilot to control the aircraft’s pitch. This could be the day.
OK, little break for science. In the years following World War II, pilots around the world desperately needed to break the sound barrier, a speed close to the speed of sound in which aerodynamics turned upside down. (Reaching speeds between 660 and 760 mph will break the sound barrier, depending on the weather conditions.) It was tough. When something is moving through the air at slower speeds, the air molecules have time to “dodge” the object. But speed up the thing – for example, an airplane – and the air molecules move closer together, compressing and increasing the density of the air at the nose of the plane. This is when things get a little scary. Shock waves form and travel rearward, creating a pressure differential that lifts the rear of the wing. The result: epic destabilization.
Before Yeager – and the Air Force stabilizer, which you can still spot on lightning-fast fighter jets – pilots lost control of their aircraft. Some have collapsed in the air. Some, including decorated British test pilot Geoffrey de Havilland Jr., died in the effort. “We weren’t getting free homes or notoriety,” Yeager later told WIRED of the efforts of the air force. “We were working our tails for $ 250 a month. Many of us died in the process. “
But that day in 1947, as Yeager sailed over the Mojave Desert in California, he fired the last two chambers of his rocket engine. The X-1’s machmeter needle, which indicated the ratio of the plane’s speed to the speed of sound, reached 1.0 – its maximum. (In truth, Yeager hit Mach 1.06.) Later, the pilot described the experience of breaking the sound barrier as “soft as a baby’s butt”.
As writer Tom Wolfe noted in Good things, his 1973 book documenting the triumphs and hardships of the daring American test pilots who propelled the country’s post-war forays into rocket technology, Yeager’s exploits were so celebrated that his “hollow print of poker in West Virginia ‘has become the model of intercom for pilots around the world. Yeager later served as a technical advisor for the film version of the book; he also made an appearance as a bartender.
Under Yeager, personnel assembled at Muroc Air Force Base (now known as Edwards Air Force Base) heard the sound of distant thunder. OK, another scientific break: As the X-1, or anything that travels super-fast, begins to move at speeds close to sound, sound waves start to build up in front of it. When the object finally passes the sound waves and all the pressure that has built up around it, these disturbing waves descend to the ground. They are loud. Maybe you’ve heard of a sound boom.