QNH, QFE and QNE - [Altitude, Height and Flight Levels explained]

The QNH and the QFE are pressure references, the QNE gives you the feet difference between your aircraft and the standard 1013hpa pressure reference.
The QNH is the pressure at the mean sea level expressed in Hpa, this pressure changes from place to place depending on the weather.
As you know with the night and day the level of the sea changes, and when talking about the QNH an average sea level between night and day has been used.
If you use the Mean Sea Level as your Altimeter pressure reference you will fly following Alitutdes.
It is important to use the QNH during the departure because you want to be separated from the obstacles and since the terrain uses the mean sea level as a reference you want to use the same reference, otherwise, the separation won't be possible.
The QFE is the pressure at your Airfield, an easy way to remember this is to take the F of QFE and associate it with the F of the Field, in this way you will never forget what the QFE is.
If you set the Pressure at your Airport as a reference you will fly following heights.
The QNE uses the Standard pressure reference of 1013,25 hpa which is used after passing the Transition Altitude.
If you use the 1013,25hpa as a Pressure reference you will fly following the Flight Levels.
Even if we commonly refer to QNE as a pressure reference if you really dive in deep you will find out that is not a pressure reference.
Watch the RUclips video below to get the full QNE detailed definition:
• QNE Is Not A Pressure ...
If you want to know more about the Transition Altitude watch the videos below:
• Altimeter Setting - [T...
• QNH and QNE Altimeter ...
As you can see an Aircraft flying at a constant level can fly using different pressure references.
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Disclaimer:
THIS VIDEO IS FOR ENTERTAINMENT PURPOSES ONLY.
NOT FOR REAL-LIFE OPERATIONS.
PLEASE REFER TO THE OFFICIAL MANUAL AND DOCUMENTATION.
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