Concorde—history’s only viable supersonic airliner—was retired in 2003. Since then, no manufacturer has managed to replicate its success.
But that could soon change.
Tuesday marked the debut flight of NASA and Lockheed Martin’s X-59—a supersonic research aircraft designed to eliminate sonic booms. The data it produces could be used to reverse the FAA’s ban on commercial supersonic flight over land, which has stood since 1973.
Commercial aircraft are permitted to fly supersonic over water. But over land, the FAA and other regulators deemed the noise from sonic booms to be too disruptive. The X-59 is built to solve that problem. It is expected to produce quieter “sonic thumps,” akin to a car door shutting in the distance.
Following a series of validation and envelope expansion flights, NASA will fly the one-of-a-kind aircraft over communities to gauge their perception of noise. The data could be used to confirm that the model’s unique design choices actually work—and could be replicated by commercial developers.
One of a Kind
The X-59 is one of the more outlandish models to take flight in recent decades.
Its most striking feature is a Pinocchio-like nose that extends about one-third of its nearly 100-foot length. It is designed to break up or “disperse” the shock waves that form in front of an aircraft moving at supersonic speed.
Also unusual is the lack of a forward-facing cockpit window. Instead, the pilot uses an external vision system that feeds imagery from high-resolution cameras to a monitor. According to NASA, the windowless design is another noise-reducing feature.
Another standout innovation is the aircraft’s top-mounted F414-GE-100 engine, giving it a smooth underside that can prevent the merging of shockwaves behind it.
The model incorporates flight-proven hardware, such as the F-15 Eagle’s life support system and F-16 Fighting Falcon’s landing gear. The airframe is composed primarily of aluminum.
The X-59 is the cornerstone of NASA’s Quiet SuperSonic Technology (QUESST) program, which launched in 2016. At the time, the space agency hoped to fly it by 2020. But though that timeline has faced delays, Tuesday’s sortie represents a major step forward.
First Flight and Next Steps
Now that the X-59 has its wings, NASA can get the ball rolling on QUESST.
Per Lockheed Martin, the aircraft took off from U.S. Air Force Plant 42 at its secretive Skunk Works facility in Palmdale, California. It landed about 30 miles away at NASA’s Armstrong Flight Research Center in Edwards, California.
NASA said in September that the debut flight would be low-altitude and reach about 240 mph, serving as a system integration test. The space agency did not release a postflight update due to the government shutdown. But Lockheed Martin said the X-59 “performed exactly as planned.”
“This aircraft is a testament to the innovation and expertise of our joint team, and we are proud to be at the forefront of quiet supersonic technology development,” OJ Sanchez, vice president and general manager of Skunk Works, said in a statement.
NASA’s Armstrong is collocated with Edwards Air Force Base (KEDW), which is expected to be the X-59’s new home. There, teams will conduct a series of validation flights to confirm its safety and airworthiness. These will be followed by envelope expansion flights, with the goal of reaching Mach 1.4—about 925 mph.
When (or if) that is achieved, NASA would conduct its own testing at Edwards’ supersonic test range. The final step will be community flights, during which it will measure noise signatures and gather feedback from people on the ground.
Ultimately, the data will be shared with the FAA and other regulators, which are facing increasing pressure to reverse supersonic flight restrictions.
“Basically, [the rule] says ‘thou shalt not exceed Mach one. And what it should say is, ‘thou shalt not make loud noises,’” Blake Scholl, CEO of Boom Supersonic, told FLYING in February.
Boom is one of a handful of companies developing a potential Concorde successor. Scholl says Overture—the company’s planned 64-80-passenger supersonic jet—will be the first.
Already, Boom says it has achieved what Scholl dubbed “boomless cruise.” Its XB-1 “Baby Boom” demonstrator in February conducted several tests that the company claims were inaudible to microphones on the ground. NASA even took part in the effort, using cameras to visualize the aircraft’s sound waves as it whizzed past.
Scholl earlier this year took a trip to Capitol Hill to plead Boom’s case to federal officials, arguing that advancements in technology have rendered the FAA’s ban moot. A group of Congressional lawmakers has also moved to lift restrictions over land.
Pressure to reverse the ban extends all the way to the White House, with President Donald Trump in June directing the FAA to repeal it. The regulator’s safety-first mentality could make that process cumbersome. But if the X-59 can gather enough data, supersonic airliners could return sooner rather than later.
