The countdown has begun for the XB-1’s “historic” first supersonic test flight that should break the sound barrier, according to Boom Supersonic.

New Concorde' attempts to break sound barrier on first supersonic flight - Boom’s inaugural XB-1 supersonic test flight takes off later today

A sleek white aircraft became the first independently developed jet to break the sound barrier Tuesday, tearing through the air tens of thousands of feet above the Mojave Desert and a crowd of delighted onlookers.