View Full Version : R/T Discipline

26th Jun 2001, 23:01
I read the thread about clearances being acknowledged at LGW incorrectly. R/T readbacks are vitally important and I am constantly amazed at the poor standard of R/T from some pilots - some, I`m afraid to say, British! I work at LATCC, West Drayton and I reckon that every 4th instruction I give has to be repeated or corrected. I know when you guys are flying a long way, you use speakers and hand-held mics, but please, not when you`re entering the London TMA at 7.30am!!! Did you know that those hand-helds make the most awful squealing noises in our headsets which can actually make you jump with shock on first transmission - they seem especially bad in the MD-80`s and BAe146`s. When we give you a heading instruction, we will say `Heading` in the instruction - can you do the sma eback please. Classic example - "London, AIRLINE123 climbing to FL150, heading 270". Controller replies "AIRLINE123, Roger, on the heading climb to Flight Level 250". Pilot reads back "Roger, 250 on the heading"
We then have to go back and confirm that it is FL250 but still heading 270 degrees. Notice also how on reply, the pilot didn`t even use his callsign. We get a lot of people being `stepped-on` so it is essential that you use your callsign whenever you reply to us. I would be very interested to hear of any pilots` views on any of these issues.

Cheers, BB!

26th Jun 2001, 23:22
Firstly, the issue of "stepped on" transmissions could be solved technically by requiring all aircraft to be fitted with "Contran", a small cost for a major contribution to safety. I believe Brittania have this system fitted to their a/c.

Secondly, as a pilot I agree with you - some of the RT one hears leaves much to be desired.

Why is this "non-standard" RT not being picked up by the companies during line checks - or don't they care?


26th Jun 2001, 23:25
As a pilot, we also get annoyed by the squealing in our headsets by those pilots who use the speakers + mikes.

I think the problem might be that pilots aren't checking that the intercom (selected on the transmit/int button) selection is actually off - this tends to cause feedback. Well, that's what happens on the 146 anyway.

Hope this helps !!

[This message has been edited by Gonegrey (edited 27 June 2001).]

27th Jun 2001, 00:02
Bewli-Begto raises a valid point, but it applies to all users, controllers included. Some years ago on descent from the north for LGW, we were "cleared Willow". As an infrequent visitor, it was not immediately clear that this meant "cleared for the Willow Arrival", and not "direct Willow". There was a difference!
Abbreviations are fine, but the instigator must ensure they are unambiguous. If you remember flight engineers (not systems operators), you will also remember that "take off power" was a no-no.

27th Jun 2001, 01:18
I don't think hand-held mikes are allowed on UK public transport aircraft are they ?

27th Jun 2001, 01:40

Yes they are.


27th Jun 2001, 01:57
While we are there, and to save my having to buy a copy of CAP 413, are we STILL required to call 'taking up the hold'?; it just seems soooooo pedantic when ATC are busy.

Capt Pit Bull
27th Jun 2001, 13:41

This seems to happen universally in UK airspace. E.G. I check in:

"London, Callsign, FL 65 climbing FL 80, Heading 085."

ATC response (assuming no change in clearance) is generally something like:

"Callsign, climb FL80, continue present heading."

or less often:

"Callsign, climb FL80, continue heading 085".

In the former case my response would have been:

"Climb FL80, continue heading, Callsign".

In the latter case, it would have been:

"Climb FL80, continue heading 085, Callsign".

This seems consistent with the idea of reading back clearances. In the first case I've been told to not change my heading, so that's what I've read back. In the secong case I've been told to fly a specific heading (which coincidentally happens to be what I was already doing), so I read back the specific value.

If I'm understanding you correctly, you are saying that its OK for ATC to tell us to continue a heading, but that we must specify what it is when we reply, otherwise you'll have to ask us.

This seems like a different standard for ATC versus Pilots. Broadly, if its not OK to simply say continue heading then this should result:

"London, Callsign, FL 65 climbing FL80, heading 085"

"Callsign, Climb FL80, continue present heading"

Now I would have to say:

"Climb FL80, confirm its heading 085, Callsign"


Now I'm not trying to split hairs or have a go, I'm a big believer in standardised RT. We are trying to get as much information content into as few words as possible, therefore the meanings of phrases must be precise.

As an aside, I don't think that standardisation on RT will ever improve unless it becomes an issue for company training departments. For example, at my mob its a big deal to reply "Checked and set" rather than "Set and Checked" in reponse to a checklist item, get it wrong and the trainer will correct you, yet at the same time you'll hear senior trainers using RT phrases that have been deleted for 10 or 15 years.



Capt Pit Bull
27th Jun 2001, 13:47

You are now separated by nothing horizontally and 1000' vertically. Your code calsign and mode C readouts on the controllers display are overlapping and cluttered.

Now is not the time to skimp on a standard call.

Go on one of Blipdrivers ATC visits,


27th Jun 2001, 14:57
Thanks Big Dog. Its just that sometimes I'm the only one who does it!

27th Jun 2001, 15:31
It really winds me up when pilots call entering the hold. The landing order is already decided by then and a call "entering the hold at time xx" is, in my opinion, a waste of RT time.
I don't know what Cap 413 says, but I'd be much happier if no-one mentioned "taking up the hold"

Mind you, when you consider the traffic levels moved by the TMA and in particular, Heathrow and Gatwick hourly movements, the majority of pilots must be really quite slick. It's important to give credit to that majority when airing the critisisms of the few.

Few Cloudy
27th Jun 2001, 16:12
Does it?

Well when I am in a holding pattern I am glad to hear any information about other aircraft entering or leaving the hold and at which level. Can't see any reason to get wound up about it.

28th Jun 2001, 00:20
Our ops manual says that we have to be wearing a headset at all times.

28th Jun 2001, 02:00
Anyone got a link to CAP413 on the web? I've searched and cannot find!

28th Jun 2001, 03:23
Sorry Few Cloudy, I guess "wound up" isn't the right phrase, it is just a frustrating use of RT time in a busy enviroment. Even with label overlap we are all monitoring the radar from far enough back to know where you are.

28th Jun 2001, 06:46
Im surprised there hasnt been a move to give ATC direction in readable text, with a monitor in the cockpit, and open up the freqs for special occasions. What little I know about incorporating that sort of technology, but I would think it would be quite possible. Sorta like internet messaging. Afterall, Boeing is introducing internet access to aircraft soon- Or would the pilots be charged 20 dollars an hour for the use? Seriously though.

28th Jun 2001, 10:22
We appear to have controllers disagreeing on the 'taking up the hold' call. Can someone quote the ATC bible please? I can see Vertigo's point in the London TMA in particular.

Foot in Mouth
28th Jun 2001, 11:22
Had a quick look in MATS pt1,However I cannot actualy find anything about holding R/T proc's for pilots.
Although it may annoy LTMA controllers I would strongly suggest that pilots report entering the hold.

i) not everybody involved in a holding stack has radar available to them.

ii) It is a good "nudge" for the ATCO when an a/c reports XXX entering hold at FL80.It informs the ATCO which levels remain ready to use.
Remember we are not allowed to use radar for seperation in the hold ,it has got to be procedural.

Capt Pit Bull
28th Jun 2001, 12:50
My point of view is based on what the trainers at LATCC said when I went on one of their seminars.


28th Jun 2001, 13:06
Can't really see the idea of readable text catching on, not until the dreaded day when ATC has direct control of aircraft via data-link!! Anyway, who would type the messages on the ground - wouldn't want to trust voice recognition software! How would you get the information about other aircrafts' relative positions/altitudes? Even when it's busy going into LHR for example, I try to keep a mental picture going (sometimes a bit fuzzy though!).

28th Jun 2001, 18:32
Hi DD. I cant really apply the idea to the job of pilots or controllers because Im not one. I just have been thinking of the idea as i read how directions get confused and readback wrong. Perhaps callsigns would be unecessary and the information would be very general(FL, Hdg, speed), and if it required readback at all, chances are it would be correct (not to say it isnt 99% of the time). The interface would have to be different than a PC to be faster. Positions could be R/T.
Just a thought considering accuracy and less congested R/T, youre the ones that can better say Yea or Nay. I guess if you can establish the link then whats to say the position of the A/C wont be tranmitted back and the ATC direction wont be interpretted and utilized by the autopilot. Then youre getting into unmanned cockpit which I reallly wouldnt like to see. Sorry I brought it up.

28th Jun 2001, 19:05
Is it necessary to be a parrot and to read back every syllable? Wouldn't it be enough to say "Airline 123, WILCO" ...unless an instruction is in doubt, or unless a new altitude is to be acknowledged?
--Controller: "Airline 123, turn right, heading two seven zero, maintain two five zero knots."
--Pilot: "Airline 123, Wilco."

28th Jun 2001, 19:15
Probably yes! What if the crew transpose the details in their minds...? "Right heading 250, speed 270 kts..." The readback is a safety check - but I grant you, it won't stop a correct readback & then incorrect action! And what about the US of A, where an ATC controller apparently is not legally obliged to amend an incorrect readback??

28th Jun 2001, 19:16
glue, executive instructions like the two you mentioned MUST be read back to,

a) check the pilot is really listening, and
b) check the controller really said the right thing!!

You pick a good example as it can often become - heading 250, speed 270kts, or even have a FL in there somewhere, even though you never gave one. On a busy frequency, lots of metal about, you have to be certain that you and them are all fully in the picture.

28th Jun 2001, 20:50
I certainly agree about reading back instructions. But do ATCOs want to hear when we check in with you what FL we are passing as well as the one we are climbing or descending to? It does seem unnecessary with Mode C, especially when things are busy.

28th Jun 2001, 21:54
Yes (if I remember correctly from Blipdriver's excellent LATCC famil visit) - a verification of your altitude (or altitude passing) is needed with each new controller/agency, primarily for a transponder check.

Bart Bandy
28th Jun 2001, 22:10
hello JSHG & EXENG. I think, if memory serves,you're both half right.Hand held mikes can only be used in controlled airspace in UK registered aircraft above F150.
(I haven't been getting out much recently!)

29th Jun 2001, 00:07
Can't be 100% sure without checking the books but I'd guess that TMA holding fixes probably constitute compulsory reporting points. The phrase 'joining the hold' is superfluous though as you will have already been instructed to do so either directly or implicitly (because you've been given an EAT). For brevity I'd suggest "callsign, fix".
RT standards do seem to be declining though and in the UK, I think one of the reasons is because of the 'continual assesment' method that many pilots would have gone through during their PPL. I thought bringing back the RT test prior to Licence issue was a great idea...after all, no-one complains about having to know the Highway Code before you pass your driving test! RT isn't rocket science and although it may seem pedantic, sticking to the standard words and phrases does work. It would have saved 577 lives in Tenerife...

29th Jun 2001, 00:57
To be perfectly honest, there are times when an a/c checks in and I think, 'c'mon, get it over with', normally when its quiet and I can see everything going on. However, when its really busy, this can be both extremely useful, and totally destructive. The initial call including both passing and cleared level takes time, valuble time, sometimes we are short of time. Sometimes though, its really useful to enable a climb for another underneath, that may be garbling and the returns cannot really be seperated. Tough one to answer.

11th Jul 2001, 00:11
Hi to all Friends Romans Countrymen & Colleages....just a bit on the above threads if I may ....
Wilco = will co-operate ....if you have not read back what you thought you heard you might co-operate with the wrong thing ...hence the need for readbacks on direct instructions......use wilco for an acknowledgement of requests....cases where if you "mis-heard" the request no harm could come to body or plane ...
Interesting topic this RT thing ....take virtually any incident / accident in Aviation and invariably there is some communication breakdown somewhere along the line ...either crew to crew or crew to ATC or a mixture of both ....training captains & ATC Training managers don't pay half as much attention to this issue as they should ...especially the former mentioned ..
A lot of what ICAO recommends often seems senseless "why should we say all that jargon" ..but do remember that all the current day RT has been built up over the years from the time when General Motors was Corporal Motors and Pontious Pilot was still a student pilot ....we should NOT question it ...but adhere to it ...and know that out of some of the worlds worst aviation disasters (remember Tenerife)the current recommendtions were built up..
Some present day popular RT "slips" that could turn out very very nasty inculde:
ATC - "XYZ taxi via A , B and C holding point rwy XX"
Pilot - " via A , B , C to rwy xx" NO MENTION IS MADE OF THE HOLDING POINT !!! hence no clearance limit was acknowledged ...ATC does'nt correct the readback because he feels hey surely they will hold at the holding point as instructed ....therefore should crew XX inadvertantly line up or enter Rwy XX" and there is an incident ...guess who swings from the gallows ...hypothetical ..NO ...it's happened !!!
Bottom line is what sounds "cool RT" is not always safe RT ...and never ever ASSUME ..because if you will end up making an ASS out of U and ME. Next time you're out there listen ....and think of the "What if's" when transsions are been broadcast ...

11th Jul 2001, 18:02
I would've thought that "safe RT" WAS "cool RT"

PPRuNe Radar
11th Jul 2001, 18:12
A few CAA leaflets which provide good advice to pilots and ATC alike......

General Aviation Safety Sense Leaflet 22 - Radiotelephony (http://www.srg.caa.co.uk/includes/ga/22leafle.pdf)

RT Discipline for Pilots & ATC (http://www.srg.caa.co.uk/includes/ga/rtdiscip.pdf)

12th Jul 2001, 07:14
You guys seen my thread "R/T phraseology in the USA" in the North america forum?

It caused quite a stir - Americans don't seem to be happy with Limeys crticising them.

12th Jul 2001, 17:09
From the other side of the world it is interesting to hear the many opinions that are in fact very similar to that elsewhere.

I believe that many of the R/T 'problems' that we have are the result that we are still hanging onto much of the R/T garbage that evolved from morse code and procedures of days gone by. Much of the ICAO procedures today are outdated and many countries use their own variation of those recommendations and in some cases make it worse.

Why on earth do we still read back the QNH?
Why should you report level passing on an enroute frequency change in a radar-identified environment? (does your transponder fail on changing frequencies?? )
Why should you repeat a heading (or any other instruction)on a frequency change if there has been no change to the instructions? (must be a UK'ism!) assigned level or altitude is fine, but that should be it - some pilots and controllers must be talking for the sake of it!
Why even do we read back as much as we presently do?
Entering the hold! Who else does that? (unless asked)

Many of the answers to these and other questions are lost in history and we only do it because that is the way it has always been done. Over the years, many words have been added but I doubt if many have been removed. Many controllers even contribute to the problem by giving instructions that need a read back when in fact the instruction may have already been given or it perhaps is not necessary at that time. And of course there are the pilots that don't know what to read back and when, so they blindly read everything back (gee I hate that). No point in reading it back unless you know what you are reading back and why?

When the traffic levels get high as they do in Europe and North America, the whole system is likely to fall apart because of the tradition of using outdated R/T calls and many unnecessary readbacks. Any wonder why many pilots in the US cut the words back.

Sure the bottom line is clear and concise communication and that should over-ride everything else, but I believe there is certainly a better way to do it. The whole package should be revised to reflect current practice and traffic levels in the 21 century.

Given that it takes ICAO around seven years to process any changes and nobody goes into bat for the greater good, it will only be fixed when we are all on data link. See what happens to your situational awareness then!

12th Jul 2001, 18:51
Following on from Glue's comment - Following a frequency change where I have told the new sector the heading (I try - honest!) If instructed to '[callsign] Speed 250, keep the heading' then normally I will reply '[callsign] speed 250, wilco' as the understanding is already there. Correct?

I think more input on BOAC's issue of 'entering the hold' may be appropriate - Would like to know the consensus on this one.

Kirk to Enterprise
12th Jul 2001, 19:26

QNH is read back as a safety check so that you have got it right. NB. CFIT rules OK!

Passing level can be useful if I miss your callsign, on the phone or coordinating with a colleague, the cleared level is a clue where to look. Not a kosha means of identification, but itís a help.

Repeating a radar heading on frequency change tells the receiving controller there must be a reason for it ie. Conflicting traffic that he may not be working, and not to take you off it until he/she is sure it is safe to do so. Also saves him/she from telling you to do it again.

Entering the hold not really necessary but is a nice nudge at times.

Replies relate to UK, but I am sure itís not much different down-under.

Count Acclaim
13th Jul 2001, 21:21
I must say I thought that the initial call confirming altitude passing was sufficient to confirm the accuracy of the transponder altitude encoding for the entire flight. Certainly for the agency concened ie NATS one confirmation is enough. Other calls of passing FLxxx for FLzzz area waste of controllers and other pilots time. As for when you pass on to another agency I don't know. Any comments appreciated.

Max Angle
13th Jul 2001, 21:42
Certainly my understanding is that passing level is only required on first contact after departure to verify mode "c".

13th Jul 2001, 21:57
QNH = ensures all a/c are at said / believed to be altitudes ...in other words if A & B are both on 1018 hpa ...and there altimeters are correct ...being verified on mode C then they should pass 1000feet if one is lets say maintaining 6000gt and the other 7000ft ALTITUDE ....altimeter setting procedures is there for two main reasons ie. everyone in a given area will/should be on the same setting ...therefore reported altitudes give the obvious results ....avoid unnecessary RA's and TA's avoiding action /grey hair etc etc
Second reason is correct QNH = missing terra firma ...
Report of altitude /level to a new radar sector on first contact is good , because ATC , unless it is a radar "handoff" of the label , is obliged by ICAO to verify mode C info for accuracy on a/c under it's control ...before the he/she uses that mode c derived info for separation ....so report the altitude and save ATC having to ask you ..for local frequently flown routes you could ask ATC which sectors are "radar hand off's and which are not"
And yes to the above thread ....safe /standard RT is cool RT .....not the Roger Roger ATC gets from some ....it's all there to cater for the weakest link + the human factor ...lot of jargon but it has saved many a butt ...

White Knight
14th Jul 2001, 11:37
Calling taking up the hold is ALWAYS a good idea - just so that other aircraft in the hold become fully aware of you . It all boils down to situational awareness, let's face it, there can be a lot of aeroplanes going round in very close proximity....

As for "stepping on" other transmissions - you can change freq. and wait for ages for a break in the talk, and when you finally think it's all clear you say your piece only to be lambasted by ATC telling you to listen out before you transmit :mad: :mad:
Take note you London sector controller on 133.17...Seriously though, I think that most people, both contollers and pilots do make the effort to get it right.

14th Jul 2001, 13:06
A question for you, London ATC controllers :

Compared to the others European countries, the UK ATC radio transmitters have a very poor quality. Any improvement in the future ?


15th Jul 2001, 15:07
Kirk... my comments on the QNH etc are still valid. You seem to have missed my point in that many of the items/phrases we read back these days have little validity in todays airspace management situation. They just occupy airtime for little practical use.

Reading back the QNH has never prevented a known accident! Setting the wrong one may have caused one, but that is a pilot procedure - not a function of ATC. In a multicrew airliner SOPS should cover such things off within the flight deck.

The bottom line is that the ICAO recommended phrases are way out of date and need to be reviewed. On the other hand, if everyone even used them it would be better!

16th Jul 2001, 00:41
Fly_by_night. The UK area systems use slightly offset frequencies from 2 or 3 transmitters at different sites. It is normally a function of the receiver if the quality is poor - not all are very good at deciphering this method of transmission. The audio quality is now worse than a few years ago,I think, due to the change in headsets used at LATCC.

16th Jul 2001, 01:24
Triadic- you are showing your location a bit. In Oz, where everyone is more or less on the same page, readbacks very rarely show up errors. But in busy multicultural environments, where English can be the second or third language in use, it is critical to have readbacks. Many errors detected.
As to mode c, it is necessary to validate it because different agencies use different equipment- Dubai App. even uses diff. to ACC. Data link is even more fraught with danger than voice- ask the guys who use it in OZ oceanic and West group and have to suffer the monthly round of 'look at all the messages that were misinterpreted and could have gone horribly wrong'.
Ferris. :(

16th Jul 2001, 01:27
For the CAA Flight Safety Commitee-

Any chance of having CAP 413 presented on the internet in the interest of Flight Safety.