WorldofAerospace.googlepages.com                                                            Contact Us | Sitemap | Home What is the Mach Number  What is the Mach Number of an Airplane and How to Calculate Mach Number Airplane Articles Mach Number - How to Calculate Mach Number In this article, we will look into how to convert different electric circuit parameters and quantities. Mach number (M) of an aircraft is an indicator which tells the speed of the aircraft relative to the speed of sound. For example, a Mach 1 means the speed of the aircraft that is its velocity is equal to local speed of sound. If both these are equal then the aircraft is said to fly at Mach 1. Similarly, if the velocity of the aircraft is twice the local speed of sound in that area then the aircraft is flying at Mach 2.   Why was the need come to define Mach numbers and why was the velocity of the aircraft not used as the indicator. The reason is that when the velocity of the aircraft becomes equal to the local speed of sound, shock waves appear on the surface of the aircraft or the so called sound barrier. At Mach 1, drag on the aircraft suddenly shoots up which is called as Drag Rise. An aircraft flying above or equal to Mach 1 is said to be under the influence of shockwaves. Below Mach 1, shock waves disappear. Mach number is defined as = M = (Velocity of the Aircraft or Vehicle) / Local Speed of Sound. or M = V/A . A Mach Number has no units.