Boom Supersonic made history today (Jan. 28) when its XB-1 jet broke the sound barrier for the first time. Boom Supersonic's chief test pilot Tristan "Geppetto" Brandenburg took off in the company's XB-1 jet from the storied Mojave Air & Space Port in California this morning under mostly clear skies. Some 11.5 minutes into the flight — the 12th overall for the XB-1 — at an altitude of around 35,000 feet (10,668 meters), the test plane exceeded Mach 1, the speed of sound, marking the first time a civil aircraft has gone supersonic over the continental United States. "This is...