A spectacular image was captured during a historic test flight. It shows the supersonic XB-1 aircraft from Boom Supersonic racing past the Sun, revealing shock waves invisible to the naked eye.
A Schlieren image captured during the test flight of the supersonic XB-1 aircraft from Boom Supersonic on February 10, 2025.
Credit: NASA/Boom Supersonic
This photograph, taken using a special technique called Schlieren imaging, required perfect coordination between the pilot and ground teams. The flight, which took place on February 10, 2025, over the Mojave Desert, allowed the aircraft to break the sound barrier three times.
Schlieren imaging, developed in 1864, makes it possible to visualize air pressure variations around objects moving at supersonic speeds. For this photo, specialized software guided the pilot to a precise position where the aircraft eclipsed the Sun, enabling NASA to capture its image using telescopes equipped with special filters.
The acoustic data collected during the flight showed that no audible sonic boom reached the ground. This discovery is crucial, as supersonic flights producing sonic booms are prohibited over populated areas in the United States.
Boom Supersonic plans to develop a supersonic aircraft whose sonic boom will not disturb populations on the ground. This aircraft, named Overture, would cut transcontinental flight times in half. The February 10 flight was the final test for the XB-1, paving the way for the construction of the Overture.
Source: Mach cutoff flight acoustic model from Pennsylvania State University
The company has already built a factory in North Carolina capable of producing up to 66 Overture aircraft per year. Several airlines, including United Airlines and Japan Airlines, have already placed orders for this aircraft.
What is Schlieren imaging?
Schlieren imaging is a photographic technique developed in 1864 by German physicist August Toepler. It makes it possible to visualize density variations in a fluid, such as air, by capturing how light is deflected by these variations.
This method is particularly useful in aeronautics for studying shock waves produced by objects moving at supersonic speeds. By making these shock waves visible, engineers can better understand and optimize the design of supersonic aircraft.
To capture a Schlieren image, special filters and telescopes are used. These instruments detect air distortions caused by shock waves, revealing details invisible to the naked eye.
The image captured during the XB-1 test flight is a perfect example of this technique, clearly showing the shock waves around the aircraft.
Why are sonic booms a problem?
Sonic booms are sound shock waves produced when an object exceeds the speed of sound. These booms can be extremely loud and disruptive to populations on the ground.
The supersonic XB-1 aircraft from Boom Supersonic, the first civil aircraft to break the sound barrier over the continental United States.
Credit: Boom Supersonic In the United States, supersonic flights producing audible sonic booms are prohibited over populated areas. This regulation has hindered the use of supersonic aircraft for commercial flights.
Boom Supersonic is working on technologies to reduce or eliminate audible sonic booms. Their goal is to enable supersonic flights without disturbing populations, paving the way for reduced flight times for passengers.
The data from the XB-1 test flight confirmed that no audible sonic boom reached the ground, marking an important step toward this goal.