The Q things

[Narada]

Here is a Q-Question for you all. We all use QNH, QFE and what not. (Ok, FE stands for Field Elevation, most likely). What does the Q stand for - anything? Or is there a history of this that has nothing to do with Q? (Just some mathematical symbol whose orgins were forgotten?)

(So far, all I can come up with was "quasi." QNH = Quasi Non Hydrostatic. Does anyone buy that?)

[Checkboard]

The Q code comes from the time that signals were transmitted in Morse Code. No word in English (don't tell me about QANTAS!) starts with a Q, and isn't followed by a U, so if the morse reciever heard a Q followed by something else - it was a 'Q code'.

[4dogs]

Checkers,

Agree on the origin. Last time I saw a listing was Vietnam time. Do you know of a full decode source?


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Stay Alive,

[email protected]

[Checkboard]

Some of them...

QRG
What's my exact frequency? What's my Rig Generating? What's the exact frequency of? The exact frequency is..

QRM
Does my transmission have interference? Your transmission has interference. This easy because interference is usually RadioMagnetic.

QRN
Is static a problem? Static is a problem. Everyone knows that static is really electrical RaiN.

QRX
RX is the standard electrical abbreviation for receive, receiver or reception. The RX is a way of asking "When will I receive your signal again?" or a way of saying "We'll re-establish contact at..".

QSO
Conversations always start with so. "SO..., how's it going?" or "SO, how are the children?". QSO is another word for contact, or communication. As a statement it's, "I can communicate with" or "I'm in contact with". As a question it's "Can I communicate with?"

QTH
What Town or you in or what Hill are you on? What's your location? My location is..

QTR
What time is it? This is a Time Request.

QFE
What is the Field Elevation pressure?

QNH
can't seem to remember this one... ;)

QDM
The exact magnetic direction of the runway.

I guess for a full decode, you will have to find an older pilot!

Hey ptero..;-)

[ATC Watcher]

. Q stands for QUESTION (in French)
The first 3 letters Q codes ( 1904 ) were the first aim at standardising communication in W/T (morse) and replaced the Merchant Navy 2 letters codes .They were all questions and all started with : What is.... ?
After the treaty of Versailles in 1918, a more complex form (additional Q codes ) were developped to cater more specifically for International aviation. The original text (like everything else in those days relating to communications ) were in French. they remained so until 1944, where PICAO and the Chicago convention established English as the commincation method and developped International R/T procedures.
Q codes in W/T were used until late 1950's especially in remote areas.The British Comet Jet was equipped with a W/T operator seat in the cockpit. the last W/T ground ATC station was Recife covering the South Atlantic and closed down in late 1960's.
The good thing about Q codes is that they eliminated the need to speak a common language when overflying or landing in other countries.The military kept them much longer than the civilians.

[BEagle]

The USAFE used to have any easy way of remembering to ask for QFE - ask the
Queer
F*****g
English,
because the rest of World uses QNH!!

[mallard]

During my time with American Airlines (sort of) they calculated a QFE, because US ATC weren't going to give them a real one, and they landed at zero feet on the altimeter.
Big enough and American enough for you?

[Canuck_AV8R]

Try this link for sone more R/T Q Codes
http://www.cam.org/~dino/ric25-qcodes.html

or this one
http://www.physik.uni-halle.de/Fachgruppen/Polymer/dl0mlu/glossary/q.shtml

Cheers


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Keep the shiny side up and the dirty side down.

Canuck Av8r
ICQ 26305263

[ATC Watcher]

The complete list of Q codes can be found in a publication called "Reglement general et additionel des radiotelecommunications," part of the Convention on International Telecommunications and published by ITU in Berne (CH) in 1938
The Aviation odes are only the series QA to QD and QF to QN, (rest is for railways, Navy and radio amateurs, etc .)
I do not have a scanner, but if someone is really interested, for a study or something else, e-mail me an adress and I could send you a photocopy of the list I have.

[jetboy]

Alright then, why do they call it a Q switch, Q pot or a Q spring. (i.e 707 feel switch) ?

[4dogs]

JB,

Because Bernoulli wasn't a ham radio operator, he didn't know about the Q Code and so after deriving his fundamental principle that "p + 1/2rhoVsquared = constant", he or someone following him had as much trouble writing the second bit as I had and said "let's simplify the second expression by making q = 1/2rhoVsquared [the good old dynamic pressure, as you well know] and we can write p + q = constant and also refer to all of those things that relate to dynamic pressure as 'q' related."

Then some technical editor decided that it was not kosher to describe a part of a feature or begin such a description with a lower case letter, and so 'q'pot became Q Pot... etc

PS I looked up a bunch of real aerody books to try to enhance my image with a heavy quote, but they all saw me coming and wrote it in full!!



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Stay Alive,

[email protected]

[WINDY7C]

QFE = Barometric pressure setting to read zero elevation on the ground. Used by the Brits, South Africa, other Colonies, and American Airlines in the USA.

QNH = Barometric pressure setting to read field elevation above mean sea level. Used by everyone else, and American Airlines on the standby altimeter.

WINDY7C

[McD]

Small correction to some of the above posts: American Airlines converted to QNH late last year. Now the Capt's, FO's, and Standby altimeter all are set to the QNH setting.

[DrSyn]

Another aviation Q-code that I haven't heard for a long while is QNE : Pressure Altitude. Still used for performance calculations, the altitude relative to standard pressure, or what it says on the clock with 1013/29.92 set.

[Hopper]

Anyone remember the Z code? Think it may have been military but can' remember. Something along the lines of ZKA ZKB INT QRK INT QRA.
Any old hams remember that?

[somewhere]

A few definitions that I remember learning are:

Q = Query
QNH = Query Normal Height
QFE = Query Field Elevation
QNE = Query Normal Elevation

I guess the "query" is the same as the "question" that someone else was talking about. Any other thoughts??

[This message has been edited by somewhere (edited 18 July 1999).]

[Genghis the Engineer]

I spent 2 weeks on a (British) aircraft carrier once, sat through the first week of met briefings before I finally worked out why they never gave QFE and did it all on QNH.

QNE is good, I always use it in flight test reports, it doesn't actually change anything but confuses anybody who probably shouldn't be reading it (flight test reports always use 1013.25mb by standard convention).

[This message has been edited by Genghis the Engineer (edited 18 July 1999).]

[Teroc]

A bit off Thread here but can anyone tell me what "Pax" stands for ?
I know its passengers but is there an individual breakdown of the letters ?

Thks
Teroc

[gaunty]

Ahem is it
QNH = Quadrantal Navigation Height set for (Altitude) ie below FLs Transition zone
QNE = Quadrantal Navigation Elevation (Flt Levels) set for FLs at standard datum
?????

[This message has been edited by gaunty (edited 22 July 1999).]

[This message has been edited by gaunty (edited 22 July 1999).]

[Checkboard]

If you set QNH, you will read the height above sea level, corrected for density up to the site of the QNH datum.

If you set QNE you will read the height above the QNE datum (the airport).

The standard pressure set for operating at Flight Levels doesn't have a 'Q' code (to the best of my knowledge) as it doesn't change.

[Oktas8]

Checkboard - either I've substantially misunderstood your last post, or you're substantially wrong. Maybe you should read the above thread?

BTW, your altimeter is not corrected for air density when you set QNH.

Cold or low, look out below!

Not trying to start a fight here,
O8

[4dogs]

Checkers,

I might just hang out with the non-combatant overcast on this one.


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Stay Alive,

[email protected]

[Checkboard]

Oooops!!

Well, there goes the cred.. I think I may have been a little under the weather when I posted that last! (I did wrestle with my conscience about doing the sneaky edit, but I will correct myself here instead.)

Read QFE for QNE in my above post.

As to the density correction, I was referring to the fact that, if you are at a field with an elevation of 5000', and you set the QNH from the tower you will see 5000' on the altimeter, regardless of temperature, ie corrected for density.

This compares with flying at (a true) 5000', and using a QNH from a sea level airport, in which case you would have to do your own density correction, so the QNH is density corrected up to the level of the QNH datum (the airport that issued it.)

[4dogs]

And standard pressure is QNE...


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Stay Alive,

[email protected]

[watford]

Sorry to resurrect this thread but I've come very late to it by way of a couple of current ones. However, I must correct a clear misconception which risks being perpetuated, most recently by 4dogs.

QNE is not a pressure setting it is an altimeter reading, measured in units of length (feet, metres, etc.) and not in millibars, hectopascals or inches.

The correct meaning of QNE is:

On landing at .... (PLACE) at .... hours, with your subscale being set to 1013.2 millibars, your altimeter will indicate .... (FIGURES AND UNITS)

ATC watcher is not quite correct in saying that all of the Q codes were questions. Since they were designed for W/T use, the interrogative form would be indicated by prefixing the code with INT (..-.-). Hence

INT QFG - Am I overhead?
QFG - You are overhead

QAA to QNZ are reserved for the aeronautical service, QOA to QQZ for the maritime service and QRA to QUZ for all services.

The Z code, mentioned by Hopper, was developed as a service code by Cable & Wireless and later taken up and expanded by others, including the military. It relates, almost exclusively, to communication by radioteletype. His example of ZKA ZKB INT QRK INT QRA translates as :

Who is controlling station?; Permission necessary before transmitting messages; What is the intelligibility of my signals?; What is the name of your station?

The response would likely be QRK0 (the intelligibility of your signals is zero), closely followed by a one-sided interview with POTS or the CRS, since that particular combination of codes would be gibberish in communications terms. Incidentally, both ZKA and ZKB are reserved for military use.

If anyone is that sad, I have a full decode of both Q and X codes from my days as a sparker.

[This message has been edited by watford (edited 27 August 2000).]

[Cornish Jack]

Watfird - nearly there! - the interrogative for the 'Q' code was IMI(barred), not INT(barred). The (barred) annotation just meant that the characters were transmitted with no spacing. The INT query function was used only with the 'Z' (military) code.

[4dogs]

Watford,

Given that I have been nailed for my ignorance (or was it my memory), I would appreciate a copy of the full Q decode if at all practicable, please.

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Stay Alive,

[email protected]

[fart]

On the lighter side of things: In our Tower we always take a "QNP" when you realise that you are not going to find someone else to blame. QNP - Quick Nervous Pee
Bye

[D Beaver]

mallard and McD

Interesting that AA used QFE. What did they do at high altitude places like Denver and Calgary? You cannot wind the altimeter back far enough - I know, I tried it once out of idle curiosity at Calgary (3550') - you run out of sub-scale.

[frankbacon]

When American and Eastern Air Lines used QFE, they actually had specially made altimeters which could be wound down far enough to read zero at Denver (alt. 5330 feet)

[jbc2001]

This link has all the Q codes including non-aviation ones. http://www.kloth.net/qcodes.htm