NASA’s X-59 supersonic aircraft is preparing for its second flight, inching its way closer to flying faster than the speed of sound without the explosive, thunder-like clap that comes with it.
A NASA team fired up the X-59’s modified engine on March 12, completing one of the last ground tests before the aircraft takes off for a second time. The aircraft’s second flight will kick off a series of flight tests scheduled for this year.
Over the coming months, NASA is aiming to fly its quiet supersonic jet faster and higher while validating the safety and performance of the aircraft. This process is known as envelope expansion, whereby engineers test a new vehicle beyond its validated limits.
The experimental aircraft, built by aerospace contractor Lockheed Martin, is designed to break the sound barrier without the loud, explosive sound known as a sonic boom. In doing so, X-59 could make quiet supersonic flight a viable option for commercial aircraft.
X-59 took to the skies for its inaugural flight on October 28, 2025, spending around one hour in the air before landing near NASA’s Armstrong Flight Research Center in Edwards, California. For its debut, the aircraft operated slower than the speed of sound at 230 miles per hour (370 kilometers per hour) and a maximum altitude of about 12,000 feet (3.6 kilometers).
After taking to the skies for the first time, NASA and Lockheed Martin got to work on post-flight maintenance and inspections of the aircraft. Engineering teams basically took the X-59 apart, removing its engine, a section of the tail known as the lower empennage, the seat, and more than 70 panels to perform inspections.
While the first flight marked the aircraft’s largest leap from the ground to airborne, the second flight will begin the gradual process of the X-59 reaching its mission parameters of about 925 miles per hour (1,488 kilometers per hour), or Mach 1.4, at an altitude of 55,000 feet (16 kilometers).
“Second flight will look a lot like the first flight,” Cathy Bahm, NASA’s project manager for the Low Boom Flight Demonstrator project, said in a statement. “We’ll start the flight at a test condition from first flight to ensure X-59 performs as expected after the maintenance phase, then we’ll start the envelope expansion by testing a little higher and faster.”
For the second flight, NASA test pilot Jim “Clue” Less will be at X-59’s controls. Less will take off and land the aircraft at Edwards Air Force Base, near X-59’s home at NASA’s Armstrong Flight Research Center in Edwards, California.
“From here on out, once we’re airborne, we can increase speed and increase altitude in small, measured chunks, looking at things as we go and not getting ahead of ourselves,” Less said in a statement. “Eventually we get to supersonic flight—a few more steps—and we’re out to Mach 1.4 at about 55,000 feet.”
Less will be accompanied by NASA test pilot Nils Larson, who will be flying nearby in a NASA F/A-18 aircraft to observe the X-59. NASA captured a wild video of the X-59’s first flight, and we can’t wait to see the ultra-thin, pointy aircraft in action once again. NASA eventually plans on flying X-59 over selected communities in the U.S. to gather data on how people on the ground perceive its quieter sound signature.
Source: Gizmodo