What Mach speed have humans reached?
What Mach speed have humans reached? In the air, the record belongs to the US Air Force's X-15 jet, which reached speeds of Mach 6.72. Translation? 4520 miles per hour. If you need a point of reference for this astronomical figure, I've got it for you: at that speed, you could circumnavigate the globe in just over 100 minutes.
Is it illegal to go Mach 1?
Currently, U.S. law prohibits flight in excess of Mach 1 over land unless specifically authorized by the FAA for purposes stated in the regulations. The two supersonic rulemaking activities would not rescind the prohibition of flight in excess of Mach 1 over land.