Douglas D-558-2 Skyrocket, 1948 U.S. Navy, public domain photograph from San Diego Air & Space Museum
This month in 1953, pilot Albert Scott Crossfield was the first person to exceed Mach 2 and in the first aircraft to do so- a Douglas D-558-2 Skyrocket.
On Nov. 20, 1953, the Skyrocket was put into position by a U.S. Navy B-29 at its launch altitude of 32,000 feet in the Calif. Mojave Desert. After dropping away from the B-29, Crossfield ignited the rocket engine reaching 72,000 feet. The Machmeter continued to climb and topped out at 2.005- just slightly more than twice the speed of sound before running out of fuel.
Who was Albert Scott Crossfield?
- After graduating from the University of Washington, Crossfield went to work for Boeing. He then served in the U.S. Navy as a flight instructor and fighter pilot during World War II, flying various aircraft.
- In 1950, Crossfield joined the National Advisory Committee for Aeronautics (NACA) High-Speed Flight Station at Edwards Air Force Base, Calif. as an aeronautical research pilot.
- Crossfield would later play a major role in the design and development of the North American X-15. They believed it capable of reaching Mach 3, and its systems were considered very dangerous. Later, he would have a series of very close calls piloting the aircraft.
- Ultimately the X-15 would achieve the highest speed, 4,520 miles per hour – Mach 6.7. On Oct. 3, 1967, it set the official world record for the highest speed ever recorded by a crewed, powered aircraft, which remains unbroken.
- Crossfield thought of himself as an aeronautical engineer, aerodynamicist, and designer. Not a celebrated death-defying pilot.
- In the 23rd Century of the Star Trek Universe, Crossfield is honored with the Crossfield class of starships.
- Actor Scott Wilson portrayed Crossfield in the 1983 film The Right Stuff.
What is Mach?
- As defined by NASA, Mach number equals object speed divided by speed of sound. It is when an object moves faster than sound.
- The Mach number describes the aircraft’s speed compared with the speed of sound in air, with Mach 1 equating to the speed of sound. It is named after Ernst Mach, an Austrian physicist, who first devised the measurement.
- As a general rule, at an air temperature of 0 degrees Celsius (32 degrees Fahrenheit), the speed of sound is approximately 331 meters per second (1,087 feet per second). Temperature changes always need to be accounted for at the time of calculating the Mach speed.
Mach 1 is 760 mph
Mach 2 is twice the speed of Mach 1 =1534.54 mph
Mach 3 is three times, and so on.
- Supersonic- objects moving at speeds greater than Mach 1.
- Transonic- when only some part of the air surrounding an object, (such as the ends of rotor blades) reaches supersonic speeds.
- Hypersonic- speeds greater than Mach 5.
- Sonic boom- above Mach 1 an aircraft will create a pressure wave. The larger the supersonic aircraft the louder the boom. Technology is being created to lessen the boom factor.