If you’ve ever wondered why airplane speeds don’t seem to be evolving much, it’s not because of a lack of interest or a lack of technology. While it is possible to build supersonic planes — ones that travel above the speed of sound — there are bans on commercial flights at such speed over the U.S. because of the noise they create. The booms caused by supersonic flight are tremendously loud, at around 110 decibels, which causes major disturbances to people on the ground.
So NASA is working on a new design of a supersonic plane which, instead of causing a sonic boom, causes a quieter sonic “thump.” The hope is that if this technology can be developed, it could enable faster flights without disturbing people living below the flight paths.
NASA’s plan is to develop the X-59 Quiet SuperSonic Technology (QueSST) plane, and recently engineers on the Commercial Supersonic Technology (CST) project tested out a small-scale model of the design in a supersonic wind tunnel at NASA Glenn to see how it would fare at high speeds.
“This is the team’s opportunity to get data at the low sound levels produced in the tunnel,” said Clayton Meyers, deputy project manager of the CST project, in a statement. “It all comes down to our ability to measure the thump.”
The testing used a model a foot and a half long, monitored by cameras and sensors in the wind tunnel. The results look promising, as they match previous computer models of the shock waves’ position and strength, suggesting the design could be effective for quieter supersonic flight.
“With the X-59, we want to demonstrate that we can reduce the annoying sonic booms to something much quieter, referred to as ‘sonic thumps,’” said John Wolter, lead researcher on the X-59 sonic boom wind tunnel test. “The goal is to provide noise and community response data to regulators, which could result in new rules for overland supersonic flight. The test proved that we don’t just have quieter aircraft design, but that we also have the accurate tools needed to predict the noise of future aircraft.”
A full-scale X-59 is currently being built, with the aim to begin test flights later this year.