Page 42 - Beginner's Guide to Aviation

[ Elevation is the measurement of height of an aircraft from sea level or airfield ] Flights report their elevation in Feat (ft) while using QNH and
Flight report their elevarion in Flight Levels (FL) while using QNE
What’s the difference between Feat (ft) and Flight Levels (FL)?
Flight levels are the apparent altitude of the aircraft’s elevation to the nearest thousand ft divided by 100.
18,000 ft is referred to as FL180 25,000 ft is referred to as FL250
When an aircraft is climbing, it uses QNH and QFE because
it is still closer to the ground. Hence, the aircraft is able to report its elevation in ft. As compared to when an aircraft is cruising, it uses QNH and QNE and reports in FL as the aircraft is now really high above ground.
For this reason, the pilot reports the aircraft’s elevation in FL to cause less confusion while communicating with the air traffic controllers. From the table, you can see the summarised alitmeter settings set of the different phases of flight.
Phases of flight
On ground and Taxiing Climbing
Cruising
Descending
Landing
Altimeter setting
QNH / QFE QNH / QNE QNH / QNE QNH / QNE QNH / QFE
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