How is altitude measured in a aeroplane?

Answer 1

As atmospheric pressure responds in a predictable manner to changes in altitude, barographs may be used to record elevation changes during an aircraft flight
Altimeter--An instrument used for measuring height.

An altimeter is an active instrument used to measure the altitude of an object above a fixed level. The traditional altimeter found in most aircraft works by measuring the air pressure from a static port. Air pressure decreases with an increase of altitude — about one millibar (0.03 inches of mercury) per 27 feet (8.23 m) close to sea level. The altimeter is calibrated to show the pressure directly as altitudes, in accordance with a mathematical model defined by the International Standard Atmosphere (ISA).
VR

Answer 2

Do you mean what kind of devices they use? If so, there are three basic methods.

The most common way to measure altitude is to measure the air pressure outside the aircraft. Air pressure decreases in a nice regular fashion as you go higher, so comparing the air pressure around the plane to the air pressure at sea level will give you a fair idea of how high you are.
This is not entirely reliable (as you know from weather maps, air pressure does change) but good enough for any normal flying.

When you need to know EXACTLY how far above the ground you are, the usual method involves radar in some form. A radar altimeter is basically a radar set that does nothing but tell you how far away the ground is. Under just the right conditions, a ground radar station can determine your altitude and tell you, but the right kind of ground radar is not all that common. Most air traffic controller depend on a pressure altimeter that sends a data signal when the plane it touched by radar (part of the transponder).

Lately, some equipment has started using GPS to tell the altitude. It's not quite as accurate as GPS positioning, but it is useful.

Hope that helped.

Answer 3

There are diverse settings for the altimeter, modifing the reference rigidity of the gauge by way of fact the atmosfere isn't consistently as defined by using ISA(international generic environment). the settings are QNE QNH QFE: QNE=the reference rigidity is the reference rigidity at sea point as defined by using ISA. this placing is significant at intense altitudes the place the the little distinction led to by using the factors isn't significant(when you consider which you ought to not stay away from mountains) and that's extremely significant that everyone airplanes have the comparable placing to maintain vertical separation. So whilst the pilot says that sentence(often being the altitude intense, on jetliners often approximately 33'000) that's the placing used. QNH= the reference rigidity is the rigidity which you are going to have at sea point that day. The tower says you this fee that's calculated, so on the airfield altitude you may examine the airfield altitude devoid of blunders. This placing is useful when you consider which you will examine on the gauge a extra properly suited altitude for that day above sea point, so immediately resembling the mountains' intense written on maps. on the runway you may examine the best altitude of the airport above seal point. QFE=the reference rigidity is the interior sight rigidity on the airfield. So on the runway you may examine 0. you may comprehend extra effective how intense you're from touching the floor, on the different hand what you examine isn't resembling altitudes on the maps. you ought to sum the airfield altitude. yet this placing is going out of use. In Europe and North united statesa. using QNH is imposed by using rules. So the two in case you're flying intense or low, the altitude is above sea point. Exceptions according to probability for helicopters in the event that they say you what the radar-altimeter signs and indicators, that's above floor point and that's not inspired by using the atmosferic rigidity of the day.

Answer 4

In addition to the usual pressure difference system, GPS can also calculate altitude.

Answer 5

By using "RADAR" i.e., radio detection and ranging.
The plane sends different radio signals to the ground in random directions. They know the speed of the signal and so they calculate the altitute by measurin the time taken by the radar signal to come back when it touches the ground.
Velocity = distance travelled / total time taken.
So, distance (altitude) = (Velocity x total time taken)
But here we need only one way distance therefore,
Altitude = (v x t)/2

Answer 6

By measuring the barometric pressure. Basically, barometric pressure is the "weight" of the atmosphere above us. When you go higher in the atmosphere, then the barometric pressure will decrease. Using this pressure, one would be able to derive the height that one is at.

Answer 7

we can also use the value of acceleration due to gravity to calculate the altitude.