How is altitude measured in a jet airplane? Or by the gage in the cockpit?

Question

How is altitude measured in a jet airplane? Or by the gage in the cockpit?

Answer 1

the standard altitude measuring equipment in all aircraft is called the ALTIMETER, and  it is measured in feet. Inside the big aircrafts now have 2 altimeters the other one is for back-up.

Answer 2

Everything you ever wanted to know about altimeters, barometric pressure and altitude measurement is here: http://www.challengers101.com/AltSetting...

Answer 3

The altimeter is operated by atmospheric pressure.  The higher you go, the less the atmospheric pressure outside; the altimeter reads the pressure against a spring to operate a dial that uses three pointers to allow it to read accurately up to altitudes higher than the airplane can ever fly.

The altimeter must be adjusted for the barometer reading, which aviation people call the "altimeter setting."  There is a small window in the dial face and a k**b for the altimeter setting.

Many modern jet airliners also have one or more radar altimeters that indicate the height above the ground in absolute terms at low altitudes.  Recent Boeing models actually talk to you:  "Two Hundred...  One Hundred...  Fifty...  Forty... Thirty... Twenty...  Ten..." on short final.  After "Ten," you are supposed to hear "bumpety-bump" as the mains touch down.

This is done with electronics about as complex as a cop's radar gun, mounted in the belly.  There are other kinds of radar altimeters, but they are all rare.  The atmospheric (or "barometric") altimeter is by far the most common.

Answer 4

from the altimeter

Answer 5

every thing is measured from sea level.

Answer 6

When flying jet aircraft, your enroute altitude is normally at 18,000 ft.or higher. In jet flying the transition altitude is 18,000 ft, or FL180.

When passing thru FL180 for a higher Flight Level, the altimeter must be set to 29.92 (standard pressure) so all aircraft will have the same setting and know their relative position with reference to all other aircraft at FL180 or higher. While in descent and approaching  FL180 for a lower altitude, the altimeter should be reset to the Qnh setting given by ATC so that the proper altitude reading will be displayed for altitudes below 18,000 ft.

Answer 7

It is measured MSL on the altimeter....in the case you have radar altimeter when you are within 2500 feet from the surface it will engage and show your actual surface to plane altitude...hope this helps...

Jonathan S

ATP-LRJET,HS-125

CFI/AGI

Answer 8

In a jet as in any other aircraft the altitude is measured by the Altimeter. The altimeter has three hands indicating 100 foot, 1000 foot and 10,000 foot increments on a scale of 0 to 9, where one rotation of the 100 foot pointer moves the 1000 foot pointer to the 1, reading 1000 foot above sea level. An adjustment k**b is used to set the current altimeter setting to correct the instrument for non standard barometric pressure. The entire instrument is actually a very simple thing. In a sealed chamber is a mechanism actuated by outside barometric pressure, moving the mechanism and with it the hands to indicate altitude. the outside air pressure is measured at the static port or static source, located on the outside of the fuselage where its location is not affected by aerodynamic anomalies and measuring actual outside barometric pressure. The ones used in jets incorporate digital interpretation and connections to the on board avionics, such as the autopilot. With the cockpits in airliners and also private aircraft going to electronic screens for the display some of the mechanical altimeters are replaced by pictures and numbers on a computer screen.

Hope this helps you out!