Go Back  PPRuNe Forums > Flight Deck Forums > Tech Log
Reload this Page >

The Q things

Wikiposts
Search
Tech Log The very best in practical technical discussion on the web

The Q things

Thread Tools
 
Search this Thread
 
Old 5th Jul 1999, 07:26
  #1 (permalink)  
Narada
Guest
 
Posts: n/a
Question The Q things


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?)
 
Old 5th Jul 1999, 07:42
  #2 (permalink)  
 
Join Date: Aug 1998
Location: Ex-pat Aussie in the UK
Posts: 5,799
Received 121 Likes on 58 Posts
Unhappy

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'.
Checkboard is offline  
Old 5th Jul 1999, 17:48
  #3 (permalink)  
4dogs
Guest
 
Posts: n/a
Unhappy

Checkers,

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


------------------
Stay Alive,

[email protected]

 
Old 5th Jul 1999, 19:05
  #4 (permalink)  
 
Join Date: Aug 1998
Location: Ex-pat Aussie in the UK
Posts: 5,799
Received 121 Likes on 58 Posts
Unhappy

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..;-)
Checkboard is offline  
Old 5th Jul 1999, 19:29
  #5 (permalink)  
Pegase Driver
 
Join Date: May 1997
Location: Europe
Age: 74
Posts: 3,694
Likes: 0
Received 0 Likes on 0 Posts
Cool

. 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.
ATC Watcher is offline  
Old 5th Jul 1999, 23:29
  #6 (permalink)  
BEagle
Guest
 
Posts: n/a
Smile

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!!
 
Old 5th Jul 1999, 23:39
  #7 (permalink)  
mallard
Guest
 
Posts: n/a
Unhappy

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?
 
Old 6th Jul 1999, 20:53
  #8 (permalink)  
Canuck_AV8R
Guest
 
Posts: n/a
Unhappy

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/Fachg...ossary/q.shtml

Cheers


------------------
Keep the shiny side up and the dirty side down.

Canuck Av8r
ICQ 26305263


 
Old 8th Jul 1999, 01:25
  #9 (permalink)  
Pegase Driver
 
Join Date: May 1997
Location: Europe
Age: 74
Posts: 3,694
Likes: 0
Received 0 Likes on 0 Posts
Cool

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.
ATC Watcher is offline  
Old 8th Jul 1999, 11:59
  #10 (permalink)  
jetboy
Guest
 
Posts: n/a
Unhappy

Alright then, why do they call it a Q switch, Q pot or a Q spring. (i.e 707 feel switch) ?
 
Old 8th Jul 1999, 18:02
  #11 (permalink)  
4dogs
Guest
 
Posts: n/a
Unhappy

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!!



------------------
Stay Alive,

[email protected]

 
Old 8th Jul 1999, 23:51
  #12 (permalink)  
WINDY7C
Guest
 
Posts: n/a
Unhappy

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
 
Old 9th Jul 1999, 17:35
  #13 (permalink)  
McD
Guest
 
Posts: n/a
Cool

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.
 
Old 11th Jul 1999, 03:45
  #14 (permalink)  
DrSyn
Guest
 
Posts: n/a
Unhappy

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.
 
Old 17th Jul 1999, 01:18
  #15 (permalink)  
Hopper
Guest
 
Posts: n/a
Unhappy

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?
 
Old 18th Jul 1999, 09:31
  #16 (permalink)  
somewhere
Guest
 
Posts: n/a
Post

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).]
 
Old 18th Jul 1999, 14:43
  #17 (permalink)  
Genghis the Engineer
Guest
 
Posts: n/a
fish

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).]
 
Old 21st Jul 1999, 12:10
  #18 (permalink)  
Teroc
Guest
 
Posts: n/a
Question

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
 
Old 22nd Jul 1999, 17:06
  #19 (permalink)  
gaunty
Guest
 
Posts: n/a
Unhappy

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).]
 
Old 23rd Jul 1999, 19:48
  #20 (permalink)  
 
Join Date: Aug 1998
Location: Ex-pat Aussie in the UK
Posts: 5,799
Received 121 Likes on 58 Posts
Unhappy

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.
Checkboard is offline  


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.