Relative bearing

[sweetnothing]

Hi can anyone please explain me the concept of
1)QDM, QDR, QTE & QUJ.

2)How to find relative bearing & thus find TO/ FROM bearing from the station.

I don't understand how to find the answers to it, but if I know the answer then I add/subtract to find the answer(cheat myself). And certainly this won't help me in the examination.

Thank You!

[Lasiorhinus]

QDM, QDR, QTE & QUJ, are archaic British codes for things that no one in aviation ever worries about anymore. Its easier to say what you want.

Relative bearing, is simply the direction the ADF needle points to, on a fixed card ADF. If it's pointing to 030, then your relative bearing is 030.

[Water Wings]

QDM, QDR, QTE & QUJ, are archaic British codes for things that no one in aviation ever worries about anymore. Its easier to say what you want.
I'd agree with you with one exception. ;)


Several odd years ago I was going through the recruitment process for an operator in Africa. An exam was provided to candidates that was fairly basic....until it asked me about Q codes. Not having ever even seen them before I guessed (multi choice) but did not do well.


Long story short I did get the job but afterwards there was a discussion as to how I had an Instrument rating and yet had no idea about Q codes. Simply not covered in our syllabus. Fast forward nearly a decade and various jobs later and I still have no idea which Q code is which!

[drpixie]

Lasiorhinus has it right - they're ancient code from the dit-dit-dah days that aren't much used. Though people still say QNH and sometimes QFE because we all love a little tradition :8

Personally, I look to find uses for:


QRM Are you being interfered with?
QRS Shall ... I ... talk ... more ... slowly?
QRR Is your auto-pilot operational?
QRZ What was that callsign again?
QSI Would you just shut-up!

[tecman]

I learned the Q-code abbreviations as a geek teenager into amateur radio, when 25 wpm Morse was still a requirement (not THAT long ago). A quaint link with the past nowadays. BTW, your explanations are much better than the official ones, DrP :)

We live with similar anachronisms in aviation weather and the associated teletype-era abbreviations, under the excuse of international standards (maybe someone, somewhere still has a teletype?). No need for the arcane..plain English is fine, although there's no shortage of conservatives wanting to defend the indefensible. Still, if there's really a hankering for the good old days, I still have that Morse key somewhere!

[Oktas8]

Wikipedia has a good albeit basic range of definitions. For those of us who passed Euro exams, some potentially useful brain space has been taken up with this antiquated nonsense. :bored: (But it would be nice to find a single Australian pilot who knows what QNE is.)

The Q codes themselves are not abbreviations. But it can be useful to think of them that way. Thus:

QDM - Q direction magnetic? (What magnetic bearing should I fly to get to the station?)
QDR - Q direct radial? (What radial am I on?)
QTE - Q True bEaring? (What bearing am I on, from the station?)
QUJ - no abbreviation, I'm not imaginative enough. What true bearing should I take, to reach you?

Obviously, QDM / QDR are reciprocals of each other for short-range queries. Same for the other two.

Relative bearings? Hard to teach without pictures, and preferably a model plane.

[drpixie]

Tecman - It's always good to find some people still know Morse - usually it's the old guys. I dare say you'll send quicker than I'll ever listen, and you recognize the codes :)

It still is useful to know the basics. One of my instructing joys was a not-very-ex military radio operator who, no matter how out of hand the flight got (and they did), could and did always quickly and correctly identify every station. :D It will keep him out of trouble one day.

[Delta_Foxtrot]

Last I heard, QNE is the ISA altimeter setting -1013.2 (well, I think it is .2 - it's been a while).

[By George]

I use to remember it as QDM bearing INBOUND and QDR bearing OUTBOUND.


The 'Q' codes go back to the days before radio when only a Morse Key was used to communicate. QRT 'stop sending' is one I remember for some strange reason. The crew in those days consisted of a Radio Operator who would bang away on a Morse Key while his nibs just flew the aeroplane.

A certain Asian airline I worked for would always use QDM and QDR termology in the SIM which would cause a level of stress amongst the younger ex-pats who tried to work out what it all means.
I understand they picked 'Q' as the lead in to the message because of its distinct sound, dah, dah dit, dah, ( here comes the Bride ). Seriously. The Poms of course, God love 'em.

[Ex FSO GRIFFO]

By George he's got it.......by George he's got it......
Q = (here comes the bride....) = Got your attention now? (Sort of...)

QDM = What is my MAG. Brg TO the station?

QDR = What is my MAG. Brg FROM the station?

QTE = What is my TRUE Brg FROM the station?

QUJ = What is my TRUE heading TO the station?

(All very important in those countries with a 'huge' mag variation....)

As in the ABC's 'Blue Hills'.......dedicated to all those...who...can remember....."
Dah de dah de dah dah daaa....

QNH and QFE still very much in existence.....and NOT to be 'confused'.....
'Ouch!'

QNE = What is your 'Flight Level'..? = Altitude with Altimeter setting on 1013.2...Used in those 'heady days' before Area QNH's and Transition Levels....like when an aircraft on a 'cross country' became airborne, climbed to its 'cruising altitude of, say 4,500ft = set alt. setting to 1013.2 for the cruise = F.L. 045.......Truly!

And, if pressed, I can even tell you WHY the system was changed......to
It involves a Fk.27 and a PA.28 near Mudgee......December '64....

In the 'early' 60's, we used to 'play a game' with the ATC guy at YSBK Twr - sorry, forgotten his name now (Noel..?) - but, was all in gooood fun at the time, requesting 'my QDM' from 2FC inbound'....
And getting 'Flashing white lights' on landing.....For a beer later....

Those 'WERE' the days...
:D

:ok:

[Jack Ranga]

Griffo, you're entitled to have forgotten all that sh!t years ago :ok:

[Ex FSO GRIFFO]

Not so JR....These days my head is like a crayfish.....

Maybe that's why 'they' call me 'crayfish' when I've had a beer or 3.....

Welcum bak!
:ok:

[propelled]

thanks Griffo and JR! good to hear the old n common sense about..
never heard of the Q codes and doesnt mean much for many.. must be days of past but glad to have learnt abount it too.. cheers guys.

[Wally Mk2]

God you blokes are showing yr age there, myself as well I guess to some degree although I ain't gunna hang myself publicly here too much:E
I've sometimes just for fun mentioned the QDM for a particular inbound track on an App chart only to have the other guy say what? I believe I first heard about the 'Q' codes from someone like Keith Hants (mentioned in another thread) I guess the youngins' don't need to know such stuff as their world is now so far removed from the good 'ole days that it matters not.

One day in the not too distant future when all the old salts have long gone the current PPruners will probably be saying remember when we had NPA's, RMP's etc with two pilots up front briefing that crap.......God how antiquated & crude where they:ok:


Wmk2

[mgahan]

Some years ago when visiting the Observatory at Greenwich to look at the chronometers - I had just finished reading "Longitude" - I wandered into the Naval Library. On sale was a 1931 edition of the "Manual of Codes": hard cover bound and embossed, 300 pages, including naval ensigns of all nations.

In it was a full listing of the Q codes used by mariners, including "I have yellow fever cases on board", "bales of wheat to unload", estimating arrival at Bombay" and the like. It may surprise some that I did not memorise all of them for future use and unfortunately I am in Jakarta at present and the book is on a bookshelf in Port Melbourne so I cannot quote the codes. I will try to have someone access the book and educate those interested!!

Going back a little less in history, some of us remember using QTE and QDM to home and let down aircraft using the CADF installed at most RAAF bases in the 1970's. Very quickly you remembered to check the position of the toggle switch before each approach.

And how many RAAF ATC students acting as CADF pilots wandering around East Sale with a hand held radio, prolonged the approach while waiting for the ASCO lady to cook a hamburger or wandered across Shagger's roses in the front yard of his MQ?

MJG

[Oktas8]

I have a pdf copy of the NATO Q code manual, if anyone is interested. It is available online but I've forgotten where it is.

Anyhow, I can email it if anyone wants a copy.

Cheers, O8

[Hempy]

QNH ~ 'nil height' (AMSL)
QFE ~ 'field elevation' (AGL)

'tis all I 'know'..

[Avgas172]

The majority of the Q codes have slipped out of common use; for example today reports such as QAU ("I am about to jettison fuel") and QAZ ("I am flying in a storm") would be voice or computerized transmissions. But several remain part of the standard ICAO radiotelephony phraseology in aviation.

Altimeter Settings

Code Meaning Sample use
QFE Atmospheric pressure at a specified datum such as airfield runway threshold. When set, the altimeter reads the height above the specified datum. Runway in use 22 Left, QFE 990 millibars
QFF Atmospheric pressure at a place, reduced to MSL using the actual temperature at the time of observation as the mean temperature.
QNE Atmospheric pressure at sea level in the International Standard Atmosphere (ISA), equal to 1013.25 mbar or hPa and used as reference for measuring the pressure altitude. When flight levels are used as an indication of altitude, 1013.25 hPa is used as mean sea level (QNH).
QNH Atmospheric pressure at mean sea level (may be either a local, measured pressure or a regional forecast pressure (RPS)). When set on the altimeter it reads altitude. Request Leeds QNH
Radio Navigation

Code Meaning Sample use
QDM Magnetic heading to a station (callsign) request QDM (callsign)[12]
QDL Series of bearings taken at regular intervals
QDR Magnetic bearing from a station (callsign) request QDR (callsign)[12]
QFU Magnetic bearing of the runway in use Runway 22 in use, QFU 220[13]
QGE Distance
QGH Controlled Descent through Clouds (Royal Air Force use)
QTE True bearing from a station (callsign) request QTE (callsign)[12]
QTF Position in relation to a point of reference or in latitude and longitude
QUJ True heading to a station
Radio Procedures

Code Meaning Sample use
QGH controller-interpreted DF let-down procedure, on UHF or VHF[14]
Maritime[edit]


Much thanks to Wikipedia & google
A172

[Kharon]

Grist to an ancient mill.

HERE (http://www.airwaysmuseum.com/Q%20code.htm)- and - HERE. (http://www.kloth.net/radio/qcodes.php)

QGF really – Dah Dit Dah

[sweetnothing]

ok. I got it. it is ancient times n all that. thank u everyone for your inputs. but I wanted to know the concept in numericals that we have in exams. Are there any good methods or flow to solve those type of questions in which we are supposed to find qdm, qdr, etc.
Also, I don't understand what is meant by " the relative bearing of station from aircraft when aircraft is heading to a different degree & different track"

[Kharon]

SN. There is some excellent reading 'on the net', there are some gifted instructors in matters aeronautical and there are certainly more patient teachers than I – however. Having watched some struggle with 'concept' I'll try to start you in the right direction. No doubt some of the learned colleagues will take over, refine and add more detail.

The clue is in the name – Relative, in relation to i.e. "considered in relation or in proportion to something else."

Look at your watch face – call 12 o' clock North (360); if you are parked at 12 and the centre of the dial is an NDB (or silo, hill, chook shed – whatever) – you are bearing 360 from that station – the station is 180 from you (Relatively). This leads you to the concept of To – From. Try that for the 1, 2, 3 etc. o'clock bearing To – From. E.g. 3 o'clock is 090 From – 270 To. 9 o'clock is 090 To – 270 From.

Lets park at 3 o'clock and turn the ADF on. Now then, you are pointed North; the ADF needle will always only do one thing – point at the station. So without us knowing where the centre of the clock is we can get 'oriented'. Heading 360, ADF pointy end at 270, so to find the station, turn through the short arc, steer 270 and 'gods willing, weather permitting', eventually you will wind up in the centre dial. If the 'clock' is too hard – think of the VOR 'rose' icon on the Jepp chart: same same..... Once you have it, the aids can be consigned to back of the bag – forever.

Don't muddle a bearing 'relative' to you with a magnetic To- From bearing. The radio mast is at 9 o'clock i.e. 270 relative to you. The track (magnetic) To – From is relative to your track – steering 030 – mast at 270 (R), To 300 - (m). So always ask - relative to what.

I forget the name of it now – think it was called a 'tracks chart', but once you can work out 'where' on the watch dial you are, no matter which way you are pointing, you are always able to work out where you are – in relation to the object of your desire, (Relatively) which is always in middle of the dial (ish).

Hope this is basically what you're after - Handing over to the Pro's.

[drpixie]

Like Kharon says - keep it simple.

The answer to your questions is: No. There are no simple formulae that you can always apply. The exam questions require you to understand the situation and apply your own logic.

Draw a little picture showing what you know. Put a tiny aeroplane on the picture, oriented appropriately. Now the situation and answers should make sense.

(I real life, and with plenty of practice, most people don't think in exam terms, it will be obvious what/where is going on - but if you don't understand the situation, you won't handle it in real life.)

[Ex FSO GRIFFO]

SN. Check your PM's.

Griffo:ok:

[sweetnothing]

this helped me alot. i understood the logic & now i am able to solve all questions. thanks again!! :)