NASA and Lockheed Martin experimental project The X-59 plane took to the skies first making history as the first supersonic aircraft designed to produce a soft “thud” instead of thunderous sonic booms.
The X-59's flight is a major step toward commercial supersonic flight, which has been banned in the United States since 1973.
The test flight was it was planned to last about an hourtook off from the Lockheed Martin Skunk Works in Palmdale, California, and landed at NASA's Armstrong Flight Research Center in Edwards, California, on October 28. The plane reached a top speed of about 240 miles per hour (386 kilometers per hour) and flew at an altitude of about 12,000 feet (3,658 meters) above the ground. During this test, aimed at testing critical systems, it did not reach supersonic speed.
According to Technical characteristics of Lockheed MartinThe X-59's top speed is Mach 1.4, or 925 mph (1,489 km/h), nearly twice as fast as the Boeing 747. It is designed to fly at altitudes of 55,000 feet (16,764 m). The aircraft has a wingspan of 30 feet (9.1 m), a height of 14 feet (4.3 m) and a whopping 100 feet (30.5 m) in length, giving it a strong resemblance to a swordfish.
From the outside, the plane's shockingly long nose appears to taper to a point, but in fact it is shaped like a chisel. The shape of the nose is designed to reshape the shock waves generated by supersonic flight, making the aircraft much quieter than the supersonic aircraft in use today. They are banned from flying over populated areas in the US due to their loud sonic booms.
Sonic booms are caused by shock waves from rapidly compressed air, similar to thunder. When a plane flies, it pushes against the air in front of it, creating pressure waves. When a plane goes supersonic, the pressure waves can't get out of the way fast enough, so they combine into one large shock wave, resulting in a sonic boom.
A controversial six-month test over Oklahoma City in 1964 showed that sonic booms from supersonic planes flying too close to the ground could break windows, cause minor damage to buildings and frighten people. At the end of the study, more than 1 in 4 people those interviewed stated that they could not learn to live with sonic booms.
To reduce the impact of the boom, the X-59's design splits a normal shock wave into several smaller shock waves, resulting in “thumps” roughly the same level as a car door slamming.
The shock waves that cause sonic booms can be seen using visualization of striaea form of specialized photography invented in 1864 by German physicist August Topler. It is based on how changes in air pressure distort light passing through it. Imaging shock waves helps us understand whether the aerodynamics of an airplane match what has been simulated using computers and small model airplanes in wind tunnels.
The X-59 is planned to go supersonic in future test flights, and if all goes according to plan, it will be used to test the public's reaction to its supersonic “strikes”, paving the way for the return of commercial supersonic flight in the US, albeit much quieter this time.
