Boom Supersonic passed a major milestone Tuesday on its path to reintroduce hypersonic commercial flights. After years of testing and refinement, a pilot flying the aerospace company’s XB-1 scale prototype finally broke the sound barrier during a livestream event—not once, not twice, but three times.

Boom Supersonic's XB-1 reached supersonic speed for the first time, proving the aircraft is capable of breaking the sound barrier.

Boom, the startup developing a new generation of supersonic aircraft, has achieved a major milestone after its test plane broke the sound barrier for the first time. The XB-1 “Baby Boom” piloted by Tristan “Gepetto” Brandenburg,