QNH
Transportation & Travel abbreviation · Aviation
| Stands for | Altimeter setting giving altitude above mean sea level (Q code) |
|---|---|
| Categories | Transportation & Travel |
QNH stands for Altimeter setting giving altitude above mean sea level (Q code), an aviation abbreviation.
Local pressure setting that makes the altimeter read the airport's elevation when on the ground and altitude above mean sea level in flight. QNH is given in hectopascals in most of the world and in inches of mercury in North America, where controllers simply call it the altimeter setting.
Example: Descend to 4,000 feet on QNH 1008, cleared for the ILS approach runway 24.
Usage notes
QNH, QFE and QNE come from the Q code, a set of three-letter radio shorthand codes devised for Morse telegraphy; the letters are not expansions, and mnemonics such as "nautical height" are memory aids only. Forgetting to switch between QNH and standard pressure at the transition level is a classic cause of altitude deviations.
Related abbreviations
More aviation abbreviations
- PFD – Primary flight display
- PIC – Pilot in command
- PIREP – Pilot report
- POH – Pilot's operating handbook
- PPL – Private pilot license
- QFE – Altimeter setting giving height above the airfield (Q code)
- RA – Resolution advisory
- RNAV – Area navigation
- RNP – Required navigation performance
- RPM – Revenue passenger miles
- RVR – Runway visual range
- RVSM – Reduced vertical separation minimum