# How high planes fly

Modern passenger planes can fly at different altitudes. Seeing in the sky flying aircraft, which takes the white trail, we often don’t realize how high it flies.

## At what altitude passenger planes fly?

Most Airliners today fly at a height of 10 to 12 thousand feet above the ground. So high they come with approximately 20 minutes of flight. This choice of the height depends on the characteristics of the atmosphere. The air at altitude over 10 thousand feet is very low, you allows you to expend less fuel to overcome drag. But at the same time, he has enough oxygen to support continuous combustion of aviation kerosene.

The height selection depends not on the aircraft commander, and dispatch service is determined and depends on the weather, the wind speed near the earth and from the direction of flight of the aircraft. The height at which a plane is called a flight level. All over the world are unified at the top flight and they can vary depending on the country, over which flies the aircraft. If the flight of the aircraft passes from West to East, for it contains only odd levels (35, 37, 39 thousand feet). If the aircraft is flying West, the trains will be, on the contrary, even (30, 36, 40 thousand feet).

Also the height of 10-12 thousand meters due to the lack of birds. Birds cause great harm to aircraft, colliding with them on small heights. At high altitudes there is no such danger.

## At what altitude to fly military aircraft?

Military aircraft fly with greater speed than passenger planes. For supersonic flight of military aircraft to fit the height of more than 13 thousand meters. At such heights is very low air density and reach the speed of sound is much easier than at a height lower than 13 thousand kilometers. For some military problems of modern military aircraft can climb to a height of more than 25 thousand kilometers. Record the maximum altitude is owned by Russian MiG-25 and is 37650 meters.

Filed in: Tip