Page 237 - PPL-engelsk 2025

Meteorology

In Denmark, we always fly (99%) with QNH on the altimeter, which is

convenient because all obstacle heights are given in relation to MSL on our

flight maps.

QFE is the pressure at the airport's official level. When the pressure at the

airport is set as a reference, the altimeter shows 0 feet when on the runway at

that airport. If you then fly a short distance, the altimeter should show 0 feet

when you land again on the same airfield as you started from.

In the UK, QFE is often used, but we do not use it in Denmark.

Be careful with obstacles such as towers, windmills, etc., as their heights on

maps are indicated as either an elevation (height above MSL) or a height (height
relative to terrain).

Here, QNH must be set as the reference to maintain the correct altitude in

relation to these.

Height above ground level is indicated with AGL after the number. For example,

"800 feet AGL" means 800 feet above ground level.

QFF is the pressure at the airport's official level reduced to MSL according to

the actual conditions.

The meteorologist calculates QFF to determine the pressure at MSL, which is

used when drawing isobars on a weather map.

QNE represents the standard pressure of 1013 hPa.

When you reach a certain altitude, all aircraft use QNE as the reference, and

they fly at flight levels.

On the next figure you can see which altitude you fly at when flying with QNH,

QNE, and QFE.

Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 237