NASA Captures Photo of Supersonic Jet Breaking the Sound Barrier

NASA has captured an image of a civil supersonic jet breaking the sound barrier using the Schlieren photography technique.

The Boom XB-1, also known as “Baby Boom,” is the first American-made civil supersonic jet and serves as a prototype for the company’s planned Overture airliner, which aims to bring back commercial supersonic travel (similar to the Concorde) but with modern efficiency and sustainability.

NASA teams on the ground captured the moment the XB-1 exceeded Mach 1 speeds on February 10 using specialist camera equipment to capture the shock waves as the jet pushed through the air. “This image makes the invisible visible,” says founder and CEO of Boom Supersonic Blake Scholl.

To capture the Schlieren image, test pilot Tristan “Geppetto” Brandenburg, had to position the XB-1 at an exact time in a precise location over the Mojave Desert in California. Brandenburg’s target was a position in front of the Sun which enabled NASA to get a picture of the changing air density as it exceeded speeds of Mach 1.

Once Brandenburg found the corrrect position using waypoints computed by NASA, the team on the ground used telescopes with special filters capable of detecting air distortions, such as shock waves, around the supersonic aircraft.

New Atlas reports that Schlieren photography was once confined to laboratories but around the year 2000, DLR Göttingen developed a system called Background Oriented Schlieren (BOS) which uses a patterned background to track how light is distorted.

It is far easier to set up as all that is required is a camera, software, and a textured background. It achieves the image by using a stable background, such as the desert floor, and using it as a reference image so that when the XB-1 flies through the same area and disturbs the air, the new image can be compared with the reference image to map air density changes.

Preventing a Sonic Boom From Hitting the Ground

The team were also eager to find out if a sonic boom, caused by the plane breaking the sound barrier, could be heard on the ground.

Boom says it demonstrated it is possible to achieve supersonic flight without the disturbance of the loud explosion-like noise on the ground. That’s because of previous research which shows if a jet breaks the sound barrier at a high enough altitude then the boom refracts in the atmosphere and never reaches the ground.

Image credits: Boom Supersonic/NASA