NASA is building a new X plane which will remove the loud thunderclap that jets make when they travel faster than sound. Due to this reasons we don’t see supersonic planes in commercially. The Low-Boom Flight Demonstration program will build the new experimental aircraft and then fly it over cities to see if it’s quiet enough to satisfy residents and regulators.“A sonic boom happens because the air doesn’t know the airplane is coming,” Peter Coen, manager for the Commercial Supersonic Technology Project in NASA’s aeronautics mission directorate. When a plane travels at speeds below the speed of sound, we can hear it coming because the sound wave is moving faster than the plane. But when the plane breaks the sound barrier, it slams into the air without any warning which creates multiple shock-waves. The shockwaves converge as they travel to the ground, sounding like a boom. He says that making small adjustments in the shape of the nose or canopy or wings, you can smear out that shockwave. So it is only a thump rather than a bang. The main thing to observe on this plane will be the long pointy nose. Aeronautical engineer Douglas Hunsaker of Utah State University uses computer to estimate how supersonic shockwaves move through the air. He says weather can be big factor in the size of the boom. He says that his colleagues at Texas A&M University are testing metal alloys that would allow a plane to change shape in the air that would mitigate the sonic boom depending on changing weather conditions.
“The thing that I’m most excited about is that NASA is moving back to this X plane concept,” Bobby Braun, dean of engineering at University of Colorado in Boulder. He added that experimental planes have been crucial to advancing aviation.
After the Concorde passenger aircraft which retired in 2003 there has been no commercial supersonic travel since. “It wouldn’t surprise me at all, if say 10 years from now, starting with supersonic business jets, and then moving into larger commercial aircraft that we’re back flying supersonically,” Braun.
NASA signed a $247.5 million contract with Lockheed Martin Aeronautics Company of Palmdale, California to build the new X plane. They are expecting the plane to be delivered by 2021.