NASA’s experimental X-59 aircraft marked a major milestone Friday, June 5, when it flew faster than the speed of sound for the first time, setting the stage for demonstrating its quiet supersonic capabilities later this year. 

NASA test pilot Jim “Clue” Less took off and landed at Edwards Air Force Base in California, reaching a top speed of approximately Mach 1.1 (713 mph) and altitude of 43,400 feet. The X-59’s flight began at 11:08 a.m. PDT and lasted 81 minutes, with the team focusing on flying qualities at both subsonic and then supersonic speeds.  

”X-59 is getting ready for its quiet supersonic debut. Since the aircraft’s first flight on Oct. 28, 2025, the team has made tremendous progress, flying 16 times in the last 90 days and getting into a steady test rhythm. In the coming days, we expect to take the next step and push to Mach 1.4,” said NASA Administrator Jared Isaacman “I’m grateful to the NASA team and Lockheed Martin Skunk Works for their help getting us to this point, and I hope this is the first of many collaborations as we rebuild NASA’s X-plane portfolio.” 

The X-59 is designed to fly at supersonic speeds while creating only a quiet thump instead of a loud sonic boom. For this flight, a NASA F‑15 chase plane flew nearby to monitor the X‑59. The loud sonic booms from the F-15 obscured any sound made 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 work to unleash supersonic flight and enable American ingenuity.” 

This first supersonic flight is a significant milestone, but an event even more critical to the mission is upcoming. In just days, the aircraft is expected to make its first “mission conditions” flight, reaching a cruising speed of Mach 1.4 (925 mph) and altitude of approximately 55,000 feet. The X-59 also will be accompanied by a chase plane for this flight.  

This speed and altitude are the base conditions for the X-59 when it will eventually fly over several U.S. communities enabling NASA to gather data about how people may perceive its quiet thump. NASA will share this data with U.S. and international regulators to help establish new data-driven noise standards to enable a future viable market for supersonic commercial flight over land. 

For the last several months, the X-59 has been participating in an ongoing series of flights where the plane has been flying at a wide range of speeds and altitudes – a process known as envelope expansion. These tests are the first phase of the X-59’s flight testing. They are focused on performance and involve chase plane monitoring. When the aircraft completes this phase it will enter another, focused on its sound profile in order to verify its quiet thump capability.  

The X-59 is the centerpiece of NASA’s Quesst mission, which aims to demonstrate quiet supersonic flight and help enable commercial supersonic flight over land worldwide. These advancements will help travelers reach their preferred destinations faster, spending less time in the air. 

Through Quesst’s development of the X-59, NASA also will deliver design tools and technology for quiet supersonic airliners that will achieve the high speeds desired by commercial operators without disturbing people on the ground. NASA will validate design tools through ground and flight testing, providing U.S. aircraft manufacturers the ability to explore new quiet supersonic concepts, and provide them with confidence that their resulting designs will meet quiet flight requirements.  

Read more about NASA’s Quesst mission and the X-59.

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From high‑speed research flights to high‑altitude science campaigns, NASA depends on aircraft that perform at their best and the ground crews who keep them mission ready.

At NASA’s Armstrong Flight Research Center in Edwards, California, specially trained maintenance crews are essential to keeping the agency’s aircraft flying safely and reliably.

This year, NASA added two F-15s and a Pilatus PC-12 to its fleet at Armstrong. These aircraft – alongside platforms such as the high-altitude ER-2s and NASA’s newest X-plane, the X-59 – reflect a wide range of capabilities. The maintenance staff is responsible for keeping each one mission ready.

“That’s the beauty of our Armstrong maintenance teams. They adapt to any type of change,” said Jose “Manny” Rodriguez, NASA Armstrong Gulfstream G-IV crew chief. “One day you could have an instrument being loaded, and the next day it may be aircraft reconfiguration, all while other aircraft systems may need fixing. They adapt and they overcome any situation.”

Each aircraft supports a specific mission, whether it’s conducting science research, serving as a support or chase aircraft, or assisting NASA rocket launches. The aircraft fly at different speeds, carry specialized hardware, and require maintenance crews to stay agile with fast-paced changes.

To ensure NASA can make aeronautics and science advancements safely, the crews work continuously, checking on the ejection seats, filling the tanks with fuel, and changing out brakes, wheels, wiring, and hardware constantly, all of which can degrade with each flight.

On any given day, an aircraft may be flight-ready for a mission, undergoing scheduled maintenance or modifications, or down for longer-term care.

There are typically multiple NASA Armstrong aircraft in the air in one day. Currently, the center’s C-20A is flying in Peru and Panama, the X-59 is often  flying twice per day with a chase plane, and the center’s ER-2 is flying in Colorado, supporting the Geological Earth Mapping Experiment (GEMx). All this work is happening at the same time, and Armstrong’s skilled maintenance staff is prepping and fixing aircraft as needed along the way.

The team includes mechanics with both military and civilian backgrounds, and the job involves a lot of on-the-job training.

Maintenance crews are composed of:

• a crew chief – the person in charge of the airplane
• an avionics technician, who specializes in navigation, communication, and flight control systems
• quality assurance personnel, who oversee the work being done
• additional mechanics assigned to each airplane

After the maintenance crew ensures the aircraft is in the best condition possible, the team tows it out to the flightline, and it becomes ready for operations. The NASA pilot assigned to the mission will walk around the aircraft with the assigned crew chief for a final safety check before flight.

“There is a crew chief assigned to every aircraft,” Rodriguez said. “The crew chief is responsible for the integrity of that aircraft, and at the end of the day, his signature and the pilot’s together are what constitutes that the aircraft is safe for flight.”

Maintenance crews track each flight to help ensure it completes the mission without returning early. If an aircraft does return to base early, the maintenance team stands ready. When it lands, the crew is right there again, helping the research team complete the mission and fixing whatever is needed to stay nimble and ready for the next flight.

“It’s difficult at times to work with different airplanes from both the civilian and military sides, but it’s very rewarding to see that we have the capability and the expertise to keep these aircraft flying,” Rodriguez said.

NASA’s home for experimental flight is welcoming more flyers to its already high-performing fleet as it continues to support science and aeronautics test missions – continuing the legacy of pioneers like Neil Armstrong.

NASA’s Armstrong Flight Research Center in Edwards, California, added multiple aircraft this year: two F-15s supersonic jets, a Pilatus PC-12 utility plane, and a T-34 turboprop trainer, which the center will use to support the agency’s advancement of aerospace research.

Throughout the center’s history, pilots have flown everything from large aircraft like the 747 Shuttle Carrier Aircraft and rocket-powered airplanes like the X-15 to high-speed repurposed fighter jets like the F-18. And after almost 80 years, flight research is still going strong in the desert today.

“Armstrong has a rich history of flight research, but it’s the multidimensional skills of the people we have here, and the knowledge they’ve built to handle very unique aircraft maintenance and modifications, that stands out,” said Darren Cole, capabilities manager for the Flight Demonstrations and Capabilities project at NASA Armstrong.

The center plays a pivotal role in worldwide airborne science missions, flying scientists and equipment from NASA, other government agencies, industry, and academia to collect measurements such as air pollution levels, glacier melt trends, and wildland fire mapping.

Scientists can manage experiments in real time aboard flying laboratories like the NASA ER-2, to collect important data with the help of Armstrong’s pilots and airborne science team.

“We all come together to make the science happen,” said Matt Berry, airborne research platforms branch chief at NASA Armstrong. “It is the agility of the Armstrong team that allows us to collaborate with scientists, get their equipment onboard, and to fly them to areas where they need to collect data.”

The center sits on Rogers Dry Lake, a 44-square-mile slat flat area used for aviation research and test operations. Rogers and the adjacent Rosamond Dry Lake have seen everything from space shuttle landings to emergency test flight recoveries. The Rogers lakebed continues to serve as an important piece of Armstrong’s test missions.

For NASA Armstrong, it all started with the first attempt by a human to fly faster than the speed of sound in the Bell X-1. In 1946, 13 employees from NASA’s predecessor agency, the National Advisory Committee for Aeronautics (NACA), arrived at what was then known as Muroc Army Airfield to prepare for the X-1 tests. A year later, NACA’s Muroc Flight Test Unit was established as a permanent facility at the airfield.

The center has gone by several names over the years, most recently changing from NASA’s Dryden Flight Research Center to NASA Armstrong in 2014. But its legacy has never shifted: The Bell X-1E, the last of the X-1 series of aircraft, now sits in front of NASA Armstrong, welcoming the newest test pilots, engineers, scientists, explorers, and dreamers. And they’re using the aircraft of today to break new barriers.

“I don’t think there is another place in the world with a more diverse fleet of aircraft. We have everything from a low-altitude powered glider to ER-2s, which are flying at high altitudes, and a multitude of aircraft in between,” Cole said.

From sourcing rare components to machining custom parts in-house, NASA Armstrong’s teams transform these aircraft into research workhorses. The center continues its crucial role in leading aeronautics testing, Earth science research, and supporting government and industry partners.