Do real pilots use QNH to mean altimiter setting?

In many forum posts I see “QNH” to refer to the setting in the window of the altimeter, so that when it is set correctly and the aircraft is on the runway, it will display the actual altitude of the airport. I also know that QNH is one of a series of Q signals invented in the early 20th century as abbreviations to make Morse code messages shorter, and to allow radio operators who spoke different languages to exchange rudimentary information.

My question is whether modern real-life pilots still say “QNH” instead of something like “altimeter setting”?

By the way, as an amateur radio operator, I have sent and received a variety of Q signals in Morse code.

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In the EU they do.

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In the US I think most ATC will just say ‘altimeter 29.92’ when they refer to the barometric pressure.

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QNH in the land of OZ

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„QNH“ is used for mbar settings while „altimeter“ means you get it in inches on the mercury bar.

As you already know QNH is a morse shorty and means nothing else than the theoretical pressure at MSL at this airport. But not less either. IMO it‘s a precise description of what you‘re talking about in opposite to the slang like „altimeter“. It‘s a bit like „set your altimeter to what I tell you and don‘t ask any questions“. I like the precision that comes with QNH and QFE.

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I think most of the world does outside of USA and Canada.

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QNH is ‘nautical height’ so gives you height above sea-level, useful when reading maps whilst VFR.
QFE is ‘field elevation’, so gives you height above the airfield, useful for joining the circuit and landing.

When ATC say altimeter isn’t that for controlled airspace so everyone has the same setting for deconfliction, and 29.92 is the standard setting for flight-levels.

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The OP’s question reminds me my first hours of flights in US as a private PPL. I learned to flight in Europe (France, Paris), so the use of the QNH was rooted even if I was well prepared for FAA phraseology.

I needed to pay attention not to use QNH instead of altimeter settings during the check ride :wink:

In Europe the phrase “QNH” is used.

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Little nitpick but officially mb is only used in UK as far as I’m aware, in Europe hPa is used although they are the same :joy:.

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:no_mouth: dude… :rofl:

You‘re right though, we‘ve always talked about hPa at theory lessons. My mum is a scuba diving instructor and she constantly talks in bars so I got used to its sound more than hectopascal :smiley:

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QNH is not “nautical height” whatever that is supposed to mean, first of all with altimeters set to local QNH, altitude above mean sea level is displayed (not height). Second I’m not sure what “nautical” is supposed to mean, altitude is in either feet or meters, not in nautical miles.

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NH, FE, DM, etc are probably meant to be abbreviations come to mind of the guy who invented them. I understand nautical height as sea level, height of sea, equal to zero. The codes are old, aviation language has evolved late, basically after Tenerife.

Disclaimer: „so I was told“ :smiley:

Actually, @keithb775406 is correct. NH is Nautical Height, just as FE is Field Elevation.
“Nautical” is not a reference to units. It is a reference to the sea. Mean Sea Level Pressure is a bit of a mouthful. Not sure who or when but somewhere along the way, altitude above sea level, became nautical height.

To add to the confusion, altitude, height and elevation are interchanged throughout the currently used terms. Internationally we cannot seem to agree on a standard measure for anything. There are more ways to measure most things than anyone can possibly hope to learn.

To answer @PristineInk5669 , there is no one, correct answer here. In North America we still use inHG (Inches of Mercury) to measure barometric pressure. As @anon50268670 said, MB (millibars) is pretty much exclusive to UK while most of the remainder of the world uses hPa (hectopascals).

If the region you are flying is using MB or hPa then they should refer to the altimeter setting as QNH, while if using inHG they should be saying Altimeter Setting. Most NA aviation authorities are pretty lazy though. I seldom here anything other that, “Current altimeter 30.01”. Some even drop “Current”.

Try building something, while farming part production to multiple international companies. Everyone has there own machining/engineering units. Conversions are usually rounded. Good luck when you get all the pieces.

Who knew that a rope is .164 meters? I thought you could cut it any length you wanted. :wink:

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I refuse to believe this is what the Q-codes mean, because they actually make sense. :rofl:

I mean, it seems like a useful mnemonic, but officially the Q-codes are NOT acronyms and there is not necessarily any correlation between the letters and the meaning.

Interestingly, both nautical height and field elevation have been in use long before the Q-codes were ever created. While the “official” derivatives may not be published, I am pretty sure the think tank that chose them were influenced by the original terms.

I can’t find any info on this, doubt it stands for nautical height as its neither of those two :joy:. There is no logic behind QFU, QGH, QDM, QTE, QUJ etc. There is only very few making sense.

QDM: Question Direction Magnetic

QDR: Question Direction Radial

But that‘s probably nothing official but made up to remember them

To break it down a bit…
Nautical height does not refer to altitude. It is a term used at one time to refer to seal level. QNH does not mean nautical height it refers to atmospheric pressure measured above nautical height. I was just hunting the internet for a reference. I have an old nautical navigation manual on my bookshelf that refers to NH when measuring tide levels with a sounding lead. I can’t seem to find an web version. Not surprising, it was originally written in the early 1600s. (Not my copy. I wish!)

QNH is not an Acronym. It is an Initialisation. An acronym is when shortened parts of words are joined (eg PanAm, FedEx) whereas an Initialisation uses the first letter from each of the words (eg NATO).

I now claim my prize for best obscure grammar nitpicking rule of the day.

[Edit: actually I’m not sure what QNH is, as on reflection it cannot be an Initialisation either as Pressure does not begin with a Q! Hopefully this will now start a fruitful discussion which will end in someone saying ‘it is all Msobos fault’]