The XB-1 broke the sound barrier for the first time over the Mojave Desert in California. During the test flight, it reached an altitude of 35,000ft before accelerating to Mach 1.1 (844mph ...
The XB-1 demonstrator has broken the speed of sound, hitting Mach 1.1. It is the first civil supersonic aircraft in US history and the first to do so since Concorde was retired in 2003. That was an ...