The instrument which indicates the aircraft's altitude, usually based on atmospheric pressure, but sometimes on radar or GPS data instead.
Questions tagged [altimeter]
119 questions
17
votes
3 answers
What is the maximum altitude of barometric altimeters?
An altimeter works by sensing static air pressure. As altitude goes up, the pressure decreases.
If I take a barometric altimeter up to space (e.g. up to satellite orbit), at what altitude does its reading become useless, i.e. the reading can no…
kevin
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Why can't you just set the altimeter to field elevation?
Why do you have to put the current altimeter setting in the kollsman window? Why can't you just set it to field elevation when you're on the ground? I understand why you would have to do it in the air.
GeckoFox1001
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11
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If left stationary at a specific height, would altimeter change the displayed value over time?
I have been reading a lot about how altimeters work, and from what I understood, most common altimeters are based of atmospheric pressure to calculate the altitude.
The question that I still have though is: If left stationary at a specific height,…
Alexus
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8
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What do the pointers on a Kollsman altimeter indicate?
In this thread: What type of altimeter is this?
there are 3 images of altimeters that have a pointer that moves around the outside diameter of the scale markings and they have another pointer that moves around the inside diameter of the scale…
curious_1
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6
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How will the altimeter read in air colder than ISA?
When flying in air which is colder than ISA (International Standard Altitude), how will the altimeter read compared to true altitude?
My manual says the altimeter will over read - why?
Ze Jibe
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5
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What is the legally accepted tolerance for altimeter errors under EASA for a VFR flight?
I have a discussion going on with a flying club member.
He states that altimeters may have an error margin of up to +/- 200ft. Example: ATC instructs you to fly 1500 feet, you would still stick to their instructions when flying 1300/1700ft as they…
Jannick
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5
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Vintage army Kollsman altimeter - any info?
I have a vintage Kollsman altimeter A.C. U.S. Army. I can't read the text on the front because of the needle arms are in the way, but might state:
Type 5
Serial No A 464.
Back plate is very hard to read, but does state:
Kollsman Brooklyn NY.
Then…
TODD W.
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3
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When flying into an area with colder air, how will the altimeter read compared to true altitude?
When flying into an area with colder air, how will the altimeter read compared to true altitude?
Air expands as the temperature increases and it compresses when the temperature decreases, shall I expect it is flying to a higher pressure area ?
PJerk
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3
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How to get the true altitude in non-standard temperature using a regular barometric altimeter?
I wondering how can we get the true altitude with non standard temperature on regular barometer altimeter, as we know that if we set Kollsman window to the current local setting the altimeter SHOULD shows the actual altitude above sea level ( True…
Aviator
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3
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What is the altitude of the nose vs tail in airplane flight?
Suppose you have an airplane flying level on a long flight. Now suppose you place one altimeter sensor in the tail, and one in the nose. Suppose you record and store these values independently (perhaps take 10 readings per second.)
And then suppose…
tdog2
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What does setting an altimeter actually do to the altitude?
I have looked at probably 10 different webpages and re watched the Sportys video on altitudes, multiple times, but I have a very fundamental question, which I am unable to wrap my head around.
Is my following understanding correct?
Pressure…
Jesh Kundem
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1 answer
Calculation of temperature correction for altimeter
I try to calculate the correction of cold temperature for altimeter , i use for this the equation 24 of the Engineering Sciences Data Unit (ESDU) publication but it give me very high number .
if i take for example the given conditions
altitude of…
Namster
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1
vote
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How does the mounting surface flatness affect radio altimeter reading?
It is recommended that the antennas be installed on flat surfaces. For some UAVs, the bottom of the fuselage is very narrow and sharply curved away from the antennas. How does it affect the measurement error?
Alex
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1
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How altitude changes with changed QNH?
How the AGL altitude changes with changed QNH? I'd like only to confirm or correct my intuition..
Airplane is maintaining certain FL with some QNH, its instruments are showing some AMSL. Now the airplane enters area with lower air pressure, but…
gusto2
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If the 10000ft pointer is reading 5 (50000ft) when you are at 10ft how do you get it back to zero
Kollsman altimeters 10000ft pointer adjustment
Phil
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