“XB-1 met all of its test objectives, including safely and successfully achieving an altitude of 7,120 feet and speeds up to 238 knots (273 mph).”
Boom calls this the return of civil supersonic aircraft to the skies. XB-1 topped out at 273 mph, slower than a regional turboprop. It is a 62-foot, one-pilot demonstrator on three GE J85 engines, and Boom has been promising this flight since 2014. Overture, the airliner that matters, still exists on renderings.