3 ms·

Still no... It's dependent on the speed of sound, which is only dependent on temperature, not specifically altitude contrary to popular belief.

• jjk166 2y ago
  Temperature varies by altitude. Mach 1 at 30,000 ft is 677mph, mach 1 at 35,000 ft is 663 mph.
  • AnarchismIsCool 2y ago
    Per ISA yes