Is the Future of Flying Supersonic? Inside NASA¡¯s Push to Make Air Travel Faster Than Ever

At a media event in January, NASA and Lockheed Martin dropped a curtain to reveal an experimental jet that could someday change the way people fly. As inspirational music played and fog crept across the floor, a plane with a long nose came into view.

The aircraft, the X-59, will hopefully fly faster than the speed of sound ¡ª?and do so relatively quietly. While the dream of routine supersonic flight for civilians seems like a futuristic one, it¡¯s actually old. If supersonic flight sounds familiar, then you might recall the Concorde: the iconic, glamorous, ultra-expensive, and ultra-fast plane that British Airways and Air France flew from 1976 to 2003. Remarkably, the Concorde¡¯s first flight was in 1969, the same year that astronauts first landed on the moon. So now, in the near future, could supersonic commercial flight once again be a real thing? If so, the X-59 is one of the most tangible representations of a new push to bring back supersonic flight for commercial passengers.

Turning a sonic boom into a ¡°gentle thump¡±

As incredible as the Concorde was ¡ª it once zipped from New York to London in two hours and 52 minutes ¡ª it was also incredibly noisy. The sonic boom it created was so loud that the aircraft was forbidden from flying over land while going supersonic. Even today, while some military aircraft can travel faster than the speed of sound, civilian planes, because of noise, haven¡¯t been able to exceed Mach 1 ¡ª the speed of sound ¡ª over land in the U.S. since the FAA banned it in 1973.

That¡¯s where the X-59 comes in. It will ideally be able to fly faster than the speed of sound, but won¡¯t make a traditional sonic boom when it does so. The X-59 is the centerpiece of a NASA program called Quesst. That program has one overarching goal: to gather data about how people on the ground react when the X-59 passes overhead at supersonic speeds, which it will hopefully accomplish in a quieter manner than a traditional supersonic aircraft. Instead of a disconcerting boom, crack, or bang sound, the X-59 will ideally make a ¡°gentle thump sound,¡± says Peter Coen, NASA¡¯s Quesst mission integration manager. When a plane flies at supersonic speeds, the aircraft generates shock waves that join up and form two bigger waves. The X-59¡¯s design, NASA hopes, will prevent shockwaves from forming in such a dramatic and loud way.

It will do this thanks to specific aspects of its physical shape that should help the aircraft slice through the air without creating shockwaves that merge. For example, the plane has a very sleek long nose, and it doesn¡¯t even have a windshield ¡ª the pilots will rely on a camera and monitor system instead to see in front of them. No windshield means no surface for the air to pile up against.

The plan is for it to start flying this year, although its initial flights will be slower than the speed of sound. If it is indeed quiet enough that people on the ground tolerate the sound once it does start going supersonic, the data gathered by NASA via the X-59 could hopefully lead to changes both in the U.S. and internationally that would allow for quieter supersonic flight over land. ¡°We want to replace the speed limit with a sound limit,¡± says Coen.

But others aren¡¯t so sure this will all work. If commercial supersonic does make a comeback, ¡°it¡¯s going to be extraordinarily controversial,¡± says Janet Bednarek, a professor at the University of Dayton who has a specialty in aviation history. She cites environmental concerns, price accessibility, and the public¡¯s sensitivity to noise as potential issues ¡ª even if the noise is indeed quieter, like the thump sound that NASA is hoping for. ¡°I¡¯m skeptical,¡± she says as to whether people will accept a sound that¡¯s more thump-like than boom-like.

The X-59 may be nearly 100 feet long, but it seats just one person: a test pilot. So while it will never carry passengers, perhaps its design will influence aircraft makers to create larger aircraft that could hold scores of people. ¡°My hope, and NASA¡¯s hope, is that eventually, this will lead to larger civil aircraft products ¡ª something the size of the Concorde or larger, that can perform supersonic overland operations as part of their design,¡± Coen adds. The Concorde carried around 100 people.

NASA is taking a slow and deliberate approach to the X-59 and its subsequent tests: They hope to be able to present data to an international aviation committee well in advance of a 2031 meeting so that at that event in nine years, its members might agree on a new permissible sound limit for supersonic flight.

Plight of the Concorde

But a handful of companies are charging ahead now, focused on creating new ways for passengers to fly at ultra-fast speeds in aircraft that would still create sonic booms as they flew, and would thus have to operate supersonically on routes over water, just like Concorde.

The most prominent outfit tackling this is called Boom Supersonic, which is working on a plane they¡¯ve dubbed Overture. Overture, if it enters service, would seat up to 80 passengers, and fly at 1.7 times the speed of sound. (The company hopes that the aircraft¡¯s first flight is in 2027.) ¡°At Boom, we¡¯re guided by one audacious mission, and that¡¯s to make the world dramatically more accessible,¡± Kathy Savitt, the company¡¯s president and chief business officer, said at an event in 2022 when announcing that Boom would build its Overture jets in Greensboro, North Carolina.

That sentiment is the big reason behind the push for supersonic commercial flight ¡ª that the world would be a better place, and smaller, if we could get to its far-flung corners more quickly. ¡°If you can spend less time traveling, you can spend more time at the place where you were going, doing what you have to, or want to, do,¡± Coen, of NASA, says. Or perhaps you venture somewhere you wouldn¡¯t otherwise have visited, because the travel time is faster.

¡°Technically, we could do it today, I think that¡¯s pretty clear,¡± says William Crossley, the head of Purdue University¡¯s School of Aeronautics and Astronautics. ¡°We¡¯d be limited on where you can fly, based on the rules about flying supersonically ¡ª there¡¯s, rightly so, a great concern about the noise from sonic booms.¡± What that means is that unless a supersonic aircraft incorporates sound-mitigating lessons from NASA¡¯s X-59, it¡¯s going to have to operate over water when cruising at Mach 1 or higher.

A big concern, he adds, is the cost of a ticket. ¡°Economically, it¡¯s going to be a really difficult proposition to make it inexpensive enough for lots of people to use it,¡± Crossley says. One of the main reasons for that is that flying at supersonic speeds requires more fuel since the aircraft experiences more drag from the air around it as it goes faster. ¡°The drag on the aircraft rises really quickly as you go to the speed of sound, and then once you get past it, it actually drops off ¡ª but it¡¯s never as low as it is when you fly below the speed of sound,¡± he explains. More drag, more fuel, more cost, higher ticket prices.

Jon Ostrower, the editor-in-chief of The Air Current, a website focused on aviation and aerospace news and analysis, echoes Crossley. The issue boils down to ¡°a passenger¡¯s willingness to pay more to fly faster,¡± he says. That¡¯s different from what people pay more for today, which is the comfort, service, and status that comes with an upgrade to business or first class. You don¡¯t get there faster, but the experience is better than it would be in economy. Maybe the time even feels like it went by quicker.

¡°I think it¡¯s really important to remember that the most single durable trend in all of aviation is not speed but efficiency and cost,¡± Ostrower adds. He says this trend applies to both mainstream airlines and budget carriers ¡ª it¡¯s all about ¡°reducing cost of operation.¡±

¡°The question is,¡± he adds, ¡°is that trend breakable?¡±

Faster than a speeding bullet

Concorde, although a product of 20th-century aviation technology, offers clues about what supersonic flight for civilians could be like if it comes back. It could actually fly twice the speed of sound, at more than 1,000 miles per hour. It cruised much higher in altitude than commercial planes do today ¡ª at 58,000 or even 60,000 feet. (Boom says Overture will also fly at 60,000 feet.) And Concorde was not for everyone. Its former chief pilot, Mike Bannister, noted in a book he wrote about flying the aircraft that ¡°Many passengers told me that Concorde was just like a club ¡ª albeit a very exclusive one.¡± He estimated their passengers were typically 80 percent business travelers.

Tickets on Concorde could cost as much as $12,000 or so for a round-trip fare.

Boom¡¯s Overture aircraft aims to fly at 1.7 times the speed of sound, and Concorde zipped along at Mach 2, but others are looking at something even more rarefied and extreme: hypersonic flight. Hypersonic refers to traveling at five times the speed of sound or more, and a company called Hermeus is one of the firms chasing that kind of travel. ¡°Long-term vision: Radically accelerate air travel with Mach-5 aircraft. So, cross the Atlantic Ocean in 90 minutes and then a little under three hours across the Pacific,¡± says AJ Piplica, the founder and CEO of the company. He says that this kind of ultra-zippy travel could lead to ¡°a significant amount of social and economic growth at a global scale¡± and is ¡°one of the big knobs you can turn for improving humanity.¡±

Hermeus is turning littler knobs before trying to turn the passenger-flight hypersonic one, though. It is starting with uncrewed aircraft called Quarterhorse and Darkhorse; the plane that could carry people someday is called Halcyon. Piplica thinks that both supersonic and hypersonic passenger flight could be a real thing in the ¡°early 2030s.¡±

Halcyon wouldn¡¯t even have regular windows. ¡°Windows at very high speeds are very, very hard,¡± he says; that¡¯s because of the heat the aircraft experiences at those speeds. He thinks that augmented reality could solve the problem by piping in an outside view to a headset in lieu of windows. ¡°Literally, just wear a Vision Pro,¡± he says. (He adds that the plane will have ¡°at least one window.¡±)

¡°Aviation tends to have a lot of sticky dreams...we can get anywhere in an hour ¡ª really, really fast. And the people who are in aviation just don¡¯t want to give up on those dreams.¡±

As for cost, he thinks the goal will be for them to produce an aircraft system that ¡°can be operated profitably at business-class prices.¡± Likewise, Boom is aiming to have airlines charge ¡°fares similar to first and business class,¡± a spokesperson says by email. It¡¯s a tough field: another company, Aerion, had hoped to build a supersonic business jet, but it folded in 2021.

¡°Aviation tends to have a lot of sticky dreams,¡± the University of Dayton¡¯s Janet Bednarek says, with one of those recurring dreams being that ¡°we can get anywhere in an hour ¡ª really, really fast. And the people who are in aviation just don¡¯t want to give up on those dreams.¡±

The dream is easy to understand, though. The Concorde once flew from New York to London in two hours and about 52 minutes, a record. Compare that to today¡¯s average flight time for the same route in the same direction: a pokey six hours and 13 minutes, according to Flightradar24.

¡°There actually is value in going that fast,¡± reflects Crossley, of Purdue University, about supersonic travel in general. ¡°I think making the world smaller is a really big deal.¡± And if it happens, it will probably be something that people have to pay for in big ways.