NASA X-59 completes first supersonic flight

NASA reached a major milestone on Friday 5 June, when its experimental X-59 aircraft travelled faster than the speed of sound for the first time. The achievement paves the way for the aircraft to demonstrate its quiet supersonic capabilities later this year.

NASA test pilot Jim “Clue” Less took off from and returned to Edwards Air Force Base in California, reaching a top speed of around Mach 1.1 (713 mph, or 1,147 km/h) at an altitude of 43,400 feet (13,228 metres).

The X-59 flight began at 11:08 PDT (Pacific Daylight Time) and lasted 81 minutes. The team initially concentrated on the aircraft’s handling characteristics at subsonic speeds before moving into the supersonic regime.

“The X-59 is preparing for its quiet supersonic debut. Since the aircraft’s first flight on 28 October 2025, the team has made tremendous progress, flying 16 times over the past 90 days and settling into a steady test cadence. In the coming days, we expect to take the next step and advance to Mach 1.4,” said NASA Administrator Jared Isaacman. “I am grateful to the NASA team and Lockheed Martin Skunk Works for helping get us to this point, and I look forward to this being the first of many collaborations as we rebuild NASA’s X-plane portfolio.”

X-59 quiet supersonic flight testing

The X-59 has been designed to fly at supersonic speeds while producing only a quiet thump rather than a loud sonic boom. During this flight, a NASA F-15 chase aircraft flew nearby to observe the X-59. The F-15’s loud sonic booms masked any sound generated by the X-59.

“The X-59’s first supersonic flight is a testament to America’s enduring leadership in science, engineering and aerospace innovation,” said Michael Kratsios, Assistant to the President for Science and Technology and Director of the Office of Science and Technology Policy. “This achievement comes as the Trump Administration continues its work to unleash supersonic flight and enable American ingenuity.”

The next X-59 mission conditions flight

While this first supersonic flight marks an important achievement, an even more critical mission event is approaching. Within just a few days, the aircraft is expected to make its first flight in “mission conditions”, reaching a cruising speed of Mach 1.4 (925 mph, or 1,488 km/h) at an altitude of about 55,000 feet (16,764 metres). A chase aircraft will also accompany the X-59 on that flight.

This speed and altitude represent the baseline operating conditions for the X-59 when it ultimately flies over several US communities, enabling NASA to gather data on how people may perceive its quiet thump. NASA will provide this information to US and international regulators to support the creation of new, data-led noise standards that could enable a viable future market for commercial supersonic flights over land.

NASA Quesst mission and commercial supersonic aviation

Over recent months, the X-59 has undertaken an ongoing series of flights across a broad range of speeds and altitudes, in a process called envelope expansion. These tests form the first stage of X-59 flight testing. They focus on performance and include monitoring by a chase aircraft. Once the aircraft has completed this phase, it will enter another phase focused on its sound profile, to confirm its quiet-thump capability.

The X-59 is the centrepiece of NASA’s Quesst mission, short for Quiet SuperSonic Technology. The programme aims to demonstrate quiet supersonic flight and help make commercial supersonic travel over land possible worldwide. These developments could allow travellers to reach their preferred destinations sooner while spending less time in the air.

Through Quesst’s development of the X-59, NASA will also provide design tools and technology for quiet commercial supersonic aircraft. These aircraft would deliver the high speeds sought by commercial operators without disturbing people on the ground.

NASA will validate its design tools through ground and flight testing, giving US aircraft manufacturers the ability to explore new quiet supersonic concepts and the confidence that their resulting designs will meet quiet-flight requirements.

NASA information