X-59: NASA's 'quiet' supersonic plane revealed

If you've heard a sonic boom recently, you probably remember it. The loud, explosion-like bang - caused by a plane flying faster than the speed of sound - can be startling, and even crack windows.

Sonic booms are part of the reason why there are no supersonic passenger planes flying today, and one of the limiting factors to the success of Concorde, which last flew in 2003. The supersonic airliner was restricted to subsonic speeds when flying over land or near coastlines, and current international regulations still limit the speed of commercial transport over land to below Mach 1, or the speed of sound, to avoid the disturbance of sonic booms over inhabited areas.

Now, NASA is working to change those regulations by transforming the boom into a "thump," paving the way for a new generation of quieter supersonic aircraft. The agency is doing so through a program called Quesst, which is the result of decades of research and is centered around a new aircraft called the X-59, which debuted Friday..

The X-59 is the latest in a series of experimental planes which include the X-1, which in 1947 became the first manned aircraft to exceed the speed of sound, and the X-15, which still holds the record for the fastest ever manned flight, set in 1967 at Mach 6.7.

The new craft was designed and built by prime contractor Lockheed Martin Skunk Works in Palmdale, California, under a $247.5 million NASA contract. With factory rollout now complete, the X-59 will now undergo integrated systems testing, engine runs, and taxi testing in preparation for first flight. It's set to take off for the first time later this year, ahead of its first quiet supersonic flight.

"In just a few short years we've gone from an ambitious concept to reality. NASA's X-59 will help change the way we travel, bringing us closer together in much less time," said NASA deputy administrator Pam Melroy in a statement.

"It will be significantly quieter than Concorde or any other supersonic aircraft that exist today," Craig Nickol, senior adviser at NASA Headquarters, told CNN in 2022. "It's extremely long and thin: It's almost 100 feet long (30.5 meters), but has a wingspan of only about 29 feet. The nose is a distinguishing feature on this aircraft: it's about a third of the length."