What is mach meter?

A Mach meter is an instrument used in aviation to measure the speed of an aircraft relative to the speed of sound. Mach is a unit of measurement representing the ratio of an object's speed to the speed of sound. When an aircraft travels faster than the speed of sound, it creates a shock wave called a sonic boom.

The Mach meter works by measuring the difference between static and dynamic air pressure. As the aircraft moves faster, the dynamic pressure increases, and the Mach meter displays the corresponding Mach number. The Mach meter typically displays the Mach number in a range from 0.2 to 1.2, where 1.0 represents the speed of sound.

Some modern Mach meters also include other features such as an altitude display and an airspeed indicator. They are essential safety instruments for pilots to maintain safe flight operations during high-speed flight.