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LHR Atis and QNH readbacks with a/c type.

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LHR Atis and QNH readbacks with a/c type.

Old 7th Jan 2010, 18:16
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fireflybob - you are indeed correct, but it isn't exactly a difficult thing to do... and surely ensuring you have copied the QNH correctly in the first place is an addition to safety?
anotherthing, lots of things are not "a difficult thing to do" but sometimes they don't get done or get done incorrectly. I think this is almost the crux of the issue. Psychologically if you have a mindset that you have already done something correctly the tendency is not to recheck. On the other hand if when you call for taxi ATC say new QNH is XXXX, I'm willing to bet most pilots will recheck the subscales. Also remember that most transport a/c have a comparator system between Capt and Fo Altimeters so if they is a signficant disagreement between indicated altitudes the system will flag this up.

I am with Jumbo Driver on this but as he had already said I would like to see the statistics for altitude busts on departure which have been caused by QNH incorrectly set. Also the breakdown on whether ATIS was available at the time (some airports don't have ATIS). Also bear in mind that some operators depart with handling pilots altimeter set to QFE! Another cause for errors!

I think this has become a circular arguement! We need to get back to some critical thinking! The question is how can we ensure that the correct QNH is set prior to departure? My answer is train the pilots to ensure that apron elevation is indicated having set QNH! This should have been done thoroughly during basic training and should be covered during routine proficiency checks.
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Old 7th Jan 2010, 21:26
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Jumbe Driver, tell you what, as it's on the ATIS, I'll stop giving out the surface wind. After all it is lot of RT time that could be saved. OK?
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Old 7th Jan 2010, 22:27
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You are correct, the argument is going round in circles - though how anyone in aviation can think that having an independant check on the one time you get QNH is beyond me.

Pilots checking QNH against threshold/apron elevation is a common sense idea and I'm frankly shocked that it isn't standard or that some pilots might even have to be 'trained' to think of it.

Maybe there is a big hole in basic training - tha sort of thing is PPL level at best!
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Old 8th Jan 2010, 01:17
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Pilots checking QNH against threshold/apron elevation is a common sense idea and I'm frankly shocked that it isn't standard or that some pilots might even have to be 'trained' to think of it.

Maybe there is a big hole in basic training - tha sort of thing is PPL level at best!
anotherthing, it is standard and it should be covered in basic training. But my supposition is that if this type of omission is occuring it can be traced back to basic training since it is basic!

I don't think there is a "big hole in basic training" but maybe some FTOs/Instructors are better at getting the message across. Whenever I have instructed basic flying (and I have done a fair bit) I emphasised that correct and disciplined operation of altimeters was critical for safe operation. Coming back to the current debate........
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Old 8th Jan 2010, 22:55
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@ Jumbodriver

Wow, are you seriously advocating that EVERY pilot get airborne without clarifying their altimeter setting?

The simple fact is that I (controller) HAVE to, and WANT to, clarify that you (pilot) have the correct setting, and sorry, but "info Kilo" is not sufficient.

Fortunatly/unfortunatly both pilots and controllers are humans, and these beings tend to make mistakes, have you never heard of transposing figures, or miss-hearing, or hearing one number and using another? Are you saying that no pilot is ever in a rush, or late, or distracted, or can't read their own writing? - get that one a lot!

Look, mistakes happen, especially where altimeters are concerned, eg

At my unit the SID climb is to a FL, NOT altitude. its clearly marked on the plates, we commuicate with the airlines about this on a regular basis, and it is a mandatory readback in the clearance, and yet... last week I had 4 (four) regular carriers climbing to x thousand feet!!

About three weeks ago:

ATC; "Nxxx, descend to altitude x thousand feet, QNH 998 millibars"

Nxxx pilot in a happy voice; "descend x thousand, altimeter to 998"

What the controller heard was;
"I am now descending to x thousand, i am changing my altimeter to 998 , and geez aren't you brits nice giving me a straight in approach and saving me 20 odd miles"

What the pilot meant was;
"I am now descending to x thousand, I am changing my altimeter to 29.98, and geez aren't you brits nice giving me the setting in inches of mercury"

I would suggest getting yourself to an ATC unit in the UK and seeing how often pilots - and controllers - make errors that are picked up by the 'other side', you may then understand how vital it is that we all clarify that we are on the same page.

WonkyV
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Old 9th Jan 2010, 13:23
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WonkyV, I have read your long post and I am well aware that readback errors occur. However, simply hammering the QNH in by repeating it ad nauseam will not solve anything.

Originally Posted by WonkyVectors
... Wow, are you seriously advocating that EVERY pilot get airborne without clarifying their altimeter setting?
No, I am not ... and if you care to read my previous posts (which it seems you may not have done) you will see that I am not suggesting that. Each pilot in a multi-crew environment will have taken the QNH from the ATIS and set it independently on his/her altimeter and, as part of normal procedure, confirmed that the airfield altitude is indicated, and that this reading is within altimeter tolerances. This should be done by each pilot independently and therefore represents two checks. Furthermore, the ATIS letter will also be read back to ensure that it contains current information at start-up - and that is then a third check.

Originally Posted by WonkyVectors
... The simple fact is that I (controller) HAVE to, and WANT to, clarify that you (pilot) have the correct setting, and sorry, but "info Kilo" is not sufficient. ...
I understand but I still maintain that one check (the ATIS letter) should be sufficient to do this for you. Reading back the QNH as well will make no difference to, say, a mis-set altimeter. Short of coming out to the cockpit to look at our altimeters to satisfy yourself that the subscales are correctly set, what else can you do? That is not your responsibility, it is ours. Simply blasting the problem by demanding another readback request is akin to saying "in case they don't understand, speak slower AND SHOUT!" It will not 1) protect against transposition errors when either setting or copying, nor 2) avoid (your example) a subsequent error by the mis-hearing or mis-setting of a cleared FL, nor 3) protect against (your further example) where an aircraft climbs on a SID to an altitude rather than a FL (or vice versa), nor 4) prevent the setting of "Hg instead of Mb by our North American friends. All these are errors which of course need to be addressed in their own way, but I would suggest they are not fundamentally related to the topic we are discussing.

I could go on, but I won't. The examples you give are fair comment on human performance and I accept these things happen in practice. I have been a professional pilot since 1970 and I fully understand what you are saying. However, simply blasting the pilot with QNH on a repeated basis will not help to remedy any of the errors you have mentioned.

By the way, I have visited quite a few ATSUs in my time so I am very familiar with what you do and also what can happen on both sides, because ATCOs and pilots are both human - what you chaps do is generally admirable and the overall standard of ATC in UK is, in my view, the best.

However, I simply do not agree that this QNH double-speak is either helpful or an aid to safety. In my opinion, it would need evidence to show that a mis-set altimeter(s) before take-off prompted an incident (like an altitude bust), and that it was caused solely or principally by a mis-set altimeter sub-scale ... and that the mis-setting could have been avoided by a further repetition of the QNH to the pilot before take-off, in addition to acknowledging the ATIS correctly. Without such corroborative evidence, I'm afraid I remain highly sceptical that this is actually a benefit to safety and nothing in this thread has so far encouraged me to change my mind.


JD
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Old 9th Jan 2010, 14:06
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It has been mandatory to read back QNH since Pontius was a Pilot.
Not in MANY other countries, it isn't...therefore, considering the Brits are the Brits...wind the clock back about fifty years and enjoy LHR, et al.
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Old 9th Jan 2010, 14:31
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JD,

'Ad nauseum' and 'repeated'... errr, does once outbound and once inbound really qualify for those epithets? I think you exaggerate just a little.

411A,

Nah, you're not worth it.
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Old 9th Jan 2010, 21:53
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Have to say, thinking about this, the number of times a pilot will report the latest ATIS letter with the wrong QNH is quite amazing. Must be 10-15 times a day to me let alone my colleagues. So just do it please. OK?
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Old 9th Jan 2010, 22:40
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Jd, I fully understand that none of us on here will change your mind. However the attitude you portray, coming as it does from a professional pilot of some 40 years standing - no doubt in a very senior position, scares the absolute bejesus poo out of me.

a) as an experienced pilot you are advocating that all aircraft depart LHR without clarification of QNH.

b) as an experienced pilot you believe that mention of a single letter indicates readback of 3 or 4 easily misheard/misread/mistyped/etc numbers.

c) as an experienced pilot I have no doubt that your crm and procedures are excellent, but you ignore the fact that other pilots have had different training/experience/distractions/procedures/pressures/knoweledge/etc

d) as an experienced pilot you wish the removal of a procedure that only asks for three seconds of your time and may correct an error, to one where no cross-checking can be applied.

e) as as an experienced pilot you wish the removal of a procedure based on your own opinion that it hasn't aided safety and .... you know what? I could go on, i had another 3 points to make, but i won't bore anyone any longer. suffice it to say what really worries me is that, as i keep saying - an experienced pilot, bemoans the fact that he has to say 4 numbers, ONCE, taking up three seconds of his time. When i'm down the back with the other 300 odd people i'd much rather have a driver who will embrace all procedures that may even remotely help safety.

WonkyV
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Old 9th Jan 2010, 22:42
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ps. What Terrain safe said.
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Old 10th Jan 2010, 09:59
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I understand you do not agree with me WonkyV but it would be more helpful if you were to debate the point, rather than insist on putting words into my mouth which almost totally misrepresent my views.

Just for the record, my comments on your points are as follows:

a) not so
b) yes - that is the intention of ATIS
c) not so
d) not so
e) no - my observations are based on the fact that no evidence has so far been produced of its efficacy

Perhaps you would like to re-read my earlier posts to see what I really think?

JD
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Old 10th Jan 2010, 10:29
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JD - the point HAS been debated ad infinitum.
The QNH has to be read back - along with other items - it is a mandatory read back.

It has become an item that is a mandatory read back due to incidents whereby this has been a causal factor.
There have been level busts caused by incorrect setting of QNH - I'm afraid that that is a fact. I'm sure if you contacted the CAA and requested data they could provide it for you.

During the entire history of aviation - procedures and phraseology have come about due to incidents, the history of which has been lost - but the lessons learnt are still in place.
You may well be fabulous and always get everything correct - but on a daily basis this is not the case.


louby
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Old 10th Jan 2010, 12:57
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loubylou, with respect I think you are also missing JD's point. As professionals I am sure that if something is mandatory then we comply! But there is nothing wrong with healthy debate about the issue because for one thing that's how we learn.

As one who has been involved in training during my aviation career for quite a while now, I know that we learn more effectively when we understand why a procedure is necessary rather than just doing things by "rote".

So please let's have the statistics - how many altitude busts have occurred on departure because QNH has been incorrectly set?

As a humorous but valid aside I like the story of children asking mum why she always cut the end of the roast off before placing in the oven. She replied "That's the way my mother always did it!". They went and asked grandma who said "That's the way my mother always did it!". Fortunately, great grandma was still living so they visited the old folks home to ask her and she she said "Because my oven was too small for it to fit in!". I think the moral of the story is that just because we have been doing something a certain way for a while and it's become established is not a reason for asking some critical questions as to why we are doing it. In NLP it's called "Starting with the end in mind".
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Old 10th Jan 2010, 21:13
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5 pages on this now?? You have got to be s****ing me. Look, its a mandatory readback. If you don't like it then take it up with CAA.
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Old 10th Jan 2010, 22:46
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Fireflybob and all.

There is noting wrong with healthy debate and in fact it should be encouraged.

The London TMA is somewhat unique in its design. As a TMA North controller, the correct QNH setting is critical to a safe operation as the majority of my SIDS have an element of a step climb to them. Both my Heathrow SIDS (BPK and BUZAD/WOBUN) climb straight to 6000 feet. However underneath I've got Luton departures climbing to 4000 of 5000, likewise Stansted's doing the same not to mention London City and Northolt.

It may seem a bit of a pain in the bum having to repeat the QNH, but trust me I have lost count of the number of times someone has called climbing to FL60 or have "bust" their level because the wrong QNH has been set. It may have not resulted in an incident, but it has on other occassions!

What is more "fail safe"? An actual QNH readback with the associated cross checks from the pilot, or an assumption that the correct QNH has been copied (often by one pilot only) from the ATIS?
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Old 10th Jan 2010, 23:50
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Wait a sec

For what it's worth, I agree with the sentiment expressed by the original poster - that's now 5 pages back. That is, it's perhaps superfluous.

I also appreciate the counter-arguments given.

Here's a question.

Given that you have to

1/ chat about the QNH on inital contact, on stand

and

2/ not give it on inital handover to approach, but instead to acknowledge and repeat on first clearance from flightlevel to an altitude

Why include the QNH in the ATIS at all?
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Old 11th Jan 2010, 14:18
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Firefly - I don't think I have missed the point - the question was why is it a mandatory readback - and I think most folk have given reasons why.

If you want it changed then contact the CAA, who make the rules.

If you want data - the get it from the CAA, who I'm sure will be able to provide it.

louby
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Old 11th Jan 2010, 16:44
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loubylou, thanks for your robust reply.
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Old 11th Jan 2010, 18:22
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Jumbo driver and fireflybob, the ATIS has been known to be wrong from time to time have you considered that in your 'proposal'?
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