NASA's 'Silent' Supersonic Airplane X-59 QueSST Has Achieved Supersonic Speed for the First Time

At the end of March, the 'silent' supersonic airplane NASA X-59 QueSST (Quiet SuperSonic Technology) took to the skies again for a second test after the one at the end of last year. Unfortunately, due to a technical problem, the test ended after a few minutes, but the space agency and technical partner Lockheed Martin had already promised new attempts throughout 2026 to continue experimenting with this new concept of supersonic airplane with reduced sonic boom.

During the test on June 5, the NASA X-59 QueSST finally surpassed the sound barrier, flying at Mach 1.1, equivalent to 1147 km/h at an altitude of 13.2 km. The test was piloted by NASA's test pilot Jim "Clue" Less, who conducted maneuvers over Edwards Air Force Base in California. The takeoff occurred around 20:08 and the mission lasted 81 minutes.

During this first attempt to reach supersonic speeds, the development team focused on flight qualities at both subsonic and supersonic speeds, proceeding to increasingly complex tests. The ultimate goal will be to fly over populated cities to verify that the sonic boom is indeed less impactful, thereby paving the way for commercial companies and new flight routes.

During the early June test, the experimental supersonic airplane was accompanied by a McDonnell Douglas F-15 Eagle from NASA to closely monitor flight conditions. Reports indicated that the F-15 was much louder compared to the X-59.

Jared Isaacman (NASA administrator) stated after the test that "X-59 is preparing for its quiet supersonic debut. Since the aircraft’s first flight on October 28, 2025, the team has made enormous progress, flying 16 times in the last 90 days and entering a steady testing rhythm. In the coming days, we expect to take the next step and push to Mach 1.4. I'm grateful to the teams at NASA and Lockheed Martin Skunk Works for their help so far, and I hope this is the first of many collaborations as we rebuild NASA's experimental aircraft (X) portfolio."

According to the space agency, in the coming weeks, the NASA X-59 QueSST is expected to conduct a more complex flight, reaching a cruising speed of Mach 1.4 (1488 km/h) and an altitude of about 16.8 km. It is important to note that this airplane will not see a commercial model. NASA will gather useful data and provide it to interested companies for the development of new models. An initial example could be Boom Supersonic, which aims to create a commercial airplane that will be cheaper than the Concorde (and only slightly slower).