How fast is one mach

But even that is subject to variation. However, scientists tend to rely on the speed of sound as measured in dry air i. As with most ratios, there are approximations and categories that are used to measure the speed of the object in relation to the sound barrier. This gives us the categories of subsonic, transonic, supersonic, and hypersonic.

This categorization system is often used to classify aircraft or spacecraft, the minimum requirement being that most of the craft classified have the ability to approach or exceed the speed of sound. For aircraft or any object that flies at a speed below the sound barrier, the classification of subsonic applies.

This category includes most commuter jets and small commercial aircraft, though some exceptions have been noted i. Since these craft never meet or exceed the speed of sound, they will have a Mach number that is less than one and therefore expressed in decimal form — i.

Typically, these aircraft are propeller-driven and tend to have high aspect-ratio slender wings and rounded features. The designation of transonic applies to a condition of flight where a range of airflow velocities exist around and past the aircraft.

These speeds are concurrently below, at, and above the speed of sound, ranging from Mach 0. Transonic aircraft nearly always have swept wings, causing the delay of drag-divergence, and are driven by jet engines. The next category is supersonic aircraft. Aircraft designed to fly at supersonic speeds show large differences in their aerodynamic design because of the radical differences in the behavior of flows above Mach 1.

These include sharp edges, thin wing sections, and tail stabilizers aka. Craft that typically have this designation include modern fighter jets, spy planes like the SR Blackbird and the aforementioned Concorde. For example, the meteor that entered the skies above the above the small town of Chelyabinsk , Russia, in February of was traveling at a speed of about In other words, the meteorite was traveling between Mach 55 and 56 when it hit our atmosphere!

Given its tremendous speed, when the meteor reached the skies above Chelyabinsk, it created a sonic boom so powerful that it caused extensive damage to thousand of building in six cities across the region.

The speed of sound varies from planet to planet. On Earth, the atmosphere is composed of mostly diatomic nitrogen and oxygen, and the temperature depends on the altitude in a rather complex way. Scientists and engineers have created a mathematical model of the atmosphere to help them account for the changing effects of temperature with altitude. Mars also has an atmosphere composed of mostly carbon dioxide. There is a similar mathematical model of the Martian atmosphere. We have created an atmospheric calculator to let you study the variation of sound speed with planet and altitude.

Here's another JavaScript program to calculate speed of sound and Mach number for different planets, altitudes, and speed. You can use this calculator to determine the Mach number of a aircraft at a given speed and altitude on Earth or Mars. This page shows an interactive Java applet which calculates the speed of sound and the mach number for an input velocity and altitude.

To change input values, click on the input box black on white , backspace over the input value, type in your new value, and hit the Enter key on the keyboard this sends your new value to the program. You will see the output boxes yellow on black change value. You can use either English or Metric units and you can input either the Mach number or the speed by using the menu buttons. Just click on the menu button and click on your selection.

If you are an experienced user of this calculator, you can use a sleek version of the program which loads faster on your computer and does not include these instructions. You can also download your own copy of the program to run off-line by clicking on this button:. Speed Mach.