When the experimental XB-1 aircraft achieved supersonic speeds on a test flight, it did not create a disruptive sonic boom – thanks to a physics phenomenon called the Mach cutoff

Boomless Cruise is based on physics known as the Mach cutoff, in which a sonic boom refracts in the atmosphere and never reaches the ground. This was achieved by breaking the sound barrier at a higher altitude, with the exact speeds varying based on the atmospheric conditions.

During the second supersonic flight of the XB-1 technology demonstrator today, the jet exceeded Mach 1 three times without a boom being detected by microphones on the desert floor below.

If you've been keeping tabs on aviation news as of late, you saw that Boom Supersonic just recently broke the sound barrier with its XB-1 demonstrator aircraft. Oddly enough, no one on the ground heard a thing during its "boomless" cruise.

Boom CEO Blake Scholl confirmed that on January 28, the XB-1 successfully broke the sound barrier three times without creating an audible sonic boom. “We broke the sound barrier