NASA has revealed new progress in its supersonic X-59 airplane. The airplane can fly at a whopping 1.4 times the speed of sound. That’s 925 miles per hour (or 1500 km/h) — while being 1000 times quieter than current supersonic planes.

The quiet supersonic airplane

Life without fast, efficient airplanes would be significantly different. We take it for granted, but today’s commercial flights are really fast. The 1950s and 1960s are sometimes referred to as the ‘golden age of flying’ but in those days, flying from England to Australia, for instance, took almost a week. Nowadays, it takes less than a day.

However, in the past couple of decades, planes haven’t really gotten much faster. A part of the problem is the so-called “sonic boom“.

When an aircraft exceeds the speed of sound, it generates shockwaves that merge and produce a loud noise, known as a sonic boom. These booms are more than just a nuisance — they cause damage. Sonic booms destroy windows and even damage buildings. They also disturb humans and wildlife, making them a significant hurdle for supersonic flight over populated areas.

The Federal Aviation Administration (FAA) has long enforced strict regulations on supersonic overland flight in the United States due to these concerns. As a result, commercial supersonic flights were confined to routes over the ocean, where the booms have no terrestrial impact. But if NASA’s X-59 project succeeds, it could pave the way for supersonic flights to operate more freely, potentially transforming the aviation landscape.

“It’s thrilling to consider the level of ambition behind Quesst and its potential benefits,” said Bob Pearce, associate administrator for aeronautics research at NASA headquarters in Washington. “NASA will share the data and technology we generate from this one-of-a-kind mission with regulators and with industry. By demonstrating the possibility of quiet commercial supersonic travel over land, we seek to open new commercial markets for US companies and benefit travelers around the world”.

A sonic “thump”

NASA’s Quesst mission aims to create the first quiet supersonic plane. The agency is collaborating with Lockheed Martin, which already unveiled the X-59 in January 2024. The plane’s sleek, needle-like fuselage, extended nose, and carefully crafted wings are engineered to prevent shockwaves from coalescing into a single, powerful boom. Instead, the X-59 is expected to produce a sound similar to a distant thud or a car door slamming. NASA refers to this as a “sonic thump”.

For now, NASA is still carefully testing the plane to see how well it can fly.

“The testing not only tells us how structurally sound the aircraft is, but also what kind of forces it can take once it is in the air,” says
Walt Silva, Senior Research Scientist at NASA Langley Research Center in Hampton, Virginia, who serves as structures lead for the X-59. “You do these tests, you get the data, and things compare well in some areas and in other areas you want to improve them,” Silva said. “So, you figure that all out and then you work towards making it better.”

Key components of the X-59 (flaps, rudders, ailerons) have already undergone intense testing. In early 2022, engineers conducted a proof test. This year, the ejection seat was installed and tested — a crucial safety measure for pilots testing the plane. Now, the aircraft is ready to advance towards the next series of tests, which will be carried out on the ground.

When it’s ready for a proper test flight, the X-59 will fly over several US cities to collect public feedback on the sound it produces. It’s almost ready for that step, but not quite yet, NASA says.

“First flights are always very intense,” said Natalie Spivey, aerospace engineer at NASA’s Armstrong Flight Research Center in Edwards, California. “There’s lots of anticipation, but we’re ready to get there and see how the aircraft responds in the air. It’ll be very exciting.”