NASA’s new supersonic plane hits key milestone

from NASA X-59 experimental aircraft is one step closer to faster-than-sound flight after the plane flew supersonic for the first time on June 5, reaching a top speed of 713 miles per hour at an altitude of 43,400 feet, the equivalent of Mach 1.1.

“Fly at supersonic speeds is a major milestone for the X-59 team,” said Cathy Bahm, project manager for the program at NASA, in a press release at the end of May, before the flight. “Completing the first flight in mission conditions is particularly significant: it is the moment when we begin to validate the aircraft in the environment for which it was designed. »

The flight lasted 81 minutes and was based at Edwards Air Force Base; NASA pilot Jim Less made this landmark exit.

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“Supersonic” is a slippery term, since the speed of sound depends on the temperature and pressure of the local atmosphere. Mach 1 represents the local speed of sound, above which the movement is considered supersonic; Mach 5 marks the transition to even faster “hypersonic” speeds. When objects move faster than the speed of sound, the pressure waves they produce are channeled toward their rear and produce a cone; if the object flies low enough for this cone to hit the Earth, the result is a loud noise called ” sonic boom.

These booms, along with huge prices, prompted the retirement in 2003 of the only supersonic airliner, the Concorde, which carried passengers starting in 1976. The plane reached a cruising speed of 1,350 mph and could fly from New York to London in less than three hours in good conditions.

For nearly a decade, NASA has been working to design a plane that could fly faster than the speed of sound without causing disruptive supersonic booms. The vehicle’s long nose is designed to disperse shock waves so that flight simply produces a “quiet supersonic thud,” as the agency described it in a late May statement, somewhere between distant thunder and a car door closing 20 feet away.

The result is the X-59, which made its first flight in October 2025 and has completed more than a dozen flights to date. Now that the

“These flights not only reinforce our confidence in the performance of the X-59, but they mark our progression toward future phases of the mission that will ultimately help shape the future of supersonic travel,” Bahm said in a late May statement.

Once this series of test flights is complete, NASA will begin a second phase of testing that will focus on the noise emitted by the aircraft, determining whether it produces the intended “quiet supersonic thud” or something closer to the unacceptable sonic booms of other high-speed vehicles. The final phase will involve moving these tests into communities, with NASA surveying residents about their thoughts on the plane’s noise.