Boom Supersonic passed a major milestone last month when its XB-1 prototype became the first civil aircraft to break the sound barrier over the continental US. Less than a month later, Chief Test Pilot Tristan “Geppetto” Brandenburg has once again surpassed Mach 1 in the experimental plane while flying as high as 36,

Boom Supersonic’s XB-1 creates a sonic boom inaudible from the ground below when flying at the exact right speed and altitude.

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.