What if you could travel from one end of the country to the other in less than half the time it takes today? With the power of supersonic flight – planes that can fly faster than the speed of sound – such a fantastic idea may soon become a reality.
Through NASA’s latest experimental project called X-59 Quiet Supersonic Technology (Quest) aircraft, the agency aims to bring supersonic technology back to the forefront of the commercial airline industry.
The capability required to break the sound barrier is typically only afforded to research and military vehicles such as fighter jets and, more recently, some electric vertical take-off and landing (eVTOL) vehicles.
And yet, with Chuck Yeager’s first record flight 75 years ago, there were several attempts to introduce the technology to the commercial sector of the airline industry. And the most famous was Concorde.
Built in the late 1970s, the supersonic airliner was ahead of its time as the plane could break speed records as it raced back and forth across the Atlantic Ocean. But while the fast-flying passengers soared across the globe, those still on the ground were left to deal with the destruction caused by startling sonic booms, loud thunder-like noises that have been known to break glass, shake buildings and cause no small amount of property damage.
“Anything supersonic that flies over land will create basically a carpet of sonic boom wherever it goes,” says Christopher Combs, assistant professor of aerodynamics at the University of Texas at San Antonio. “This could be [as] we saw a very strong one [and] disturbing people in their homes.’
Because sound waves can travel through the air when the craft is flying at or above the speed of sound, the air molecules near the wings are disturbed and cannot move out of the way fast enough. This creates a pressure wave that combines and propagates, creating a continuous shock wave that follows behind the aircraft during its flight path.
Years earlier, public fears about the destructive nature of the booms had already prompted the Federal Aviation Administration to ban flights from coast to coast. But after Concorde was decommissioned (in part because of how expensive it had become to fly) in 2003, the concerns were enough to end the resurgence of supersonic passenger travel.
Combs also noted that while cost and noise were factors, many of the issues surrounding supersonic technology revolved around efficiency, because “when you’re going at that speed, you’re not burning fuel as efficiently.”
Despite these setbacks, NASA’s goal with the X-59 is to create a supersonic vehicle that can transform these once-destructive sonic booms into barely perceptible sonic booms.
Almost 100 feet long and 30 feet wide, the vessel’s unique shape makes for a quieter cruise. It allows it to spread out the shock waves, which prevents the waves from merging when they reach the ground. Unlike a typical aircraft, the X-59’s high-thrust engines are located on top of the ship to direct noise from the wandering audience below.
By drastically reducing the volume of the aircraft, the sound of the aircraft overhead will echo as loud as car door slam almost undetectable by busy passers-by, says Dave Richwine, deputy project manager for technology for the Low Boom Flight Demonstrator project, which oversaw development of the X-59.
“You’ll hear something like a heartbeat,” Richwine says. “Or you might not even hear it at all if you’re in a noisy environment like the city.”
By removing these barriers, the agency hopes to usher in a new era of civil air transport. By now, experts have also figured this out the demand for technology exists and replacing our current domestic flights with more efficient ones can help improve the diminishing expectations of the airline industry.
Of the three phases of the X-59 mission, the aircraft is currently still in its first phase as NASA engineers continue to test its performance as well as its safety. For example, because the nose of the plane is so long and angular, pilots can’t see out of the heads-up display. Instead, they will have to use NASA’s eXternal Vision System (XVS), a combination of sensors and computers and HD displays to ensure they can navigate safely in the sky.
Still, Richwine says NASA hopes to have the plane flying by the end of this year. Once operational, the second phase involves choosing a select number of communities to fly the aircraft over to test its ability to fly quietly in a range of different conditions.
As an experimental aircraft, the X-59 will never carry passengers in its lifetime, but the data it collects during the second phase of testing could be used to set new sound-based rules and regulations for US and international airplanes. The mission’s potential success could be just the boost future aircraft developers need to help get supersonic technology approved for commercial travel.
Still, it will be years before commercial supersonic flight becomes readily available to the average person, and the market for it will likely follow in the footsteps of the commercial space sector. Wealthier citizens will have continued access before commercialization makes it available to the general public.
Still, Richwine imagines that as the decades go by and supersonic technology becomes more common, travelers could buy a ticket and find more joy in their travels than they do today.
“It will matter,” Richwine says. “If [we] you may be flying a plane in 20 years and that flight lasts only half the time. That sure would be nice.