What do altimeters tell you?

An altimeter is a device that measures altitude—a location’s distance above sea level. Most altimeters are barometric, meaning they measure altitude by calculating the location’s air pressure.

What is altimeter ATC?

It is a pressure setting used by pilots, air traffic control (ATC), and low frequency weather beacons to refer to the barometric setting which, when set on an aircraft’s altimeter, will cause the altimeter to read altitude above mean sea level within a certain defined region.

What is altimeter pressure?

The altimeter setting is the pressure value to which an aircraft altimeter scale is set so that it will indicate the altitude (above mean sea level) of the aircraft on the ground at the location for which the pressure value was determined.

Why do pilots need the altimeter?

Weather changes that affect temperatures and air pressures cause the complications in understanding and using an altimeter. This is why an aircraft’s actual height above mean sea level is its true altitude while what the altimeter says is the indicated altitude.

Why do pilots set altimeter?

This is handy when you are at an airport without weather reports. What happens when you are flying to an airport that’s not at sea level? You need the correct setting before you land. In this case, the altimeter setting amounts to what a barometer at that location would read at sea level at that time.

Can GPS detect altitude?

Global Positioning System (GPS) receivers can also determine altitude by trilateration with four or more satellites. … In hiking and climbing, it is common to find that the altitude measured by GPS is off by as much as 400 feet (122 metres) depending on satellite orientation.

Why is the standard altimeter setting 2992 the standard pressure?

Why Is 29.92 The Standard Altimeter Setting? Standard pressure is 1013.25 hectopascals (hPa) which is equivalent to 29.92 inches of mercury (Hg). This setting is equivalent to the atmospheric pressure at mean sea level (MSL).

What does a barometer reading of 2992 mean?

A barometer reading below 29.92”Hg is a low pressure system and usually means air is warming and humidity is increasing. Low pressure systems tend to bring clouds, rain and snow storms. High pressure systems tend to bring clear skies and a calm atmosphere. Why 29.92 above 18,000 feet?

What is the standard altimeter setting?

– Airplane Academy Why Is 29.92 The Standard Altimeter Setting? Standard pressure is 1013.25 hectopascals (hPa) which is equivalent to 29.92 inches of mercury (Hg). This setting is equivalent to the atmospheric pressure at mean sea level (MSL).

Is 2992 the real pressure over 18000 ft?

Now, as you pass 18,000 ft (in the US) you need to switch your altimeter setting to 29,92. Why? Is that the real pressure over 18,000? No. But above that altitude it’s not really necessary to know your real altitude.