"Airport elevation XX" feet, cleared approach"

[Telstar]

Is what I think the phrase was going into Prestwick tonight. I queried the reason the airfield elevation was passed to me and was told "It's a new proceedure we have to do".

I am sure there is a very good reason for it, but my pea sized brain hasn't been able to come up with the reason, especially when it's printed on the approach plates.

[Defruiter]

In the phraseology section of MATS, it says:

"Descend on the ILS, QNH (pressure) millibars, elevation (number) feet."

Most units dont give the QNH and elevation and just "descend on the ILS".

(in the college of knowledge, we had to say it all the time when we cleared someone for the ILS - it got annoying, like you said, the pilot should know it, it is there on the chart)

Perhaps Prestwick has been told for some reason to start doing it?

Just a guess...Correct me if I am wrong

[Spitoon]

So, is the MATS wrong or are most units wrong?

[Defruiter]

Who knows...

It's not the only thing thats different though - There are a few things that are done differently to what MATS says...

[bermudatriangle]

just a courtesy for those who land on QFE.common practice around eastern med,turkey and most subcontinent airfields, to be told airfield elevation by controllers.just a reminder that may or may not be of any info.

[HEATHROW DIRECTOR]

Used to do it yonks ago on London Approach both for London Airport (Heathrow) and Northolt but then it changed and we ceased to do it... can't recall why.

[Hooligan Bill]

This may have something to do with the publication of ATSIN 104 Change To UK Altimeter Setting Procedures :- Link below
http://www.caa.co.uk/application.aspx?catid=33&pagetype=65&appid=11&mode=detail&id=2766

[flower]

To get around not having to say the airfield elevation on the RT a number of Units transmit it on the ATIS. I've always thought it a nonsense here in the UK and yet another waste of valuable RT time better used elsewhere. The elevation is after all published on the approach plates and one assumes aircrew are quite capable of looking at that.

[Telstar]

‘Aircraft are to be given the appropriate QNH prior to commencing an approach. When requested by the pilot, or local procedures require, the appropriate QFE or aerodrome / threshold elevation shall be given.’

We were doing a QNH based ILS so do I understand it that it is only to be passed when performing an ILS based on a QFE? So in my case it was given in error?

[Chilli Monster]

Looks like the boys and girls of Prestwick need to re-read the ATSIN (along with a couple of posters here ;) )

Aircraft are to be given the appropriate QNH prior to commencing an approach. When requested by the pilot, or local procedures require, the appropriate QFE or aerodrome / threshold elevation shall be given..

If the pilot didn't request it, and I doubt there's a good reason for putting it in as a local instruction (we don't - and we're higher) why were they giving it?

[Standard Noise]

Maybe my poor fuzzy brain has missed something here, but why did they give the 'airfield elevation' and not threshold, assuming of course, that Telstar was flying the type he has stored in his profile and not a chopper?:confused:
I were always taught to give threshold for runway landers and airfield for 'off runway' landers ie helos with skids.

[Telstar]

Sorry, it was threshold elevation. I was not flying a chopper.

[spekesoftly]

In years gone by, the majority of pilots in the UK used QFE on final approach, and ATC TX'd (or were supposed to TX!) the elevation to those relatively few pilots that elected to remain on QNH. Over the past 20 years or so, the use of QNH by public transport operators in UK airspace has gradually become almost universal, and the majority of ATCOs abbreviated their TXs accordingly. ATSIN 104 gives official acknowledgement, but MATS does not yet reflect this.

I don't understand the rationale of passing elevation with QFE (see post #5). Passing elevation with QNH is not really an error (see post #9), but ATSIN 104 suggests to me that it is no longer required, unless requested by the pilot etc.

[2 sheds]

There is NO rationale in passing aerodrome/threshold elevation and QFE. SRG got it wrong and when attcked by numerous people about the wording of the ATSIN, cancelled and replaced it. The worrying aspect is why did they get it wrong in the first place, it's not a difficult concept!

[Hooligan Bill]

UK AIP ENR 1-7-3 para 5.3.4 still states "The threshold elevation of each instrument runway that is 7 ft or more below the aerodrome elevation is given at AD 2.12. The barometric pressure setting to be used for landing on such a runway will be passed by ATC as QNH . . . . threshold elevation . . . . ,
or QFE . . . . threshold . . . . ."

Thefore irrespective of what the ATSIN says in these cases the threshold elevation should still be passed. However, this has always been the case and is therefore not a "new procedure".

[spekesoftly]

Brilliant! So the UK MATS is contradicted by ATSIN 104, which is contradicted by the UK AIP.

No room for any ATCO/Pilot confusion there then! :rolleyes:

[Skipness One Echo]

Oddly enough the've ALWAYS done this at Prestwick going back to 1990 at least when NATs were running the show. I know because I was doing my O Grades at the time and got puzzled by the fact that the Runway 31 elevation was 66 ft ( it is now 65 ft I believe - is the country sinking we need to know? ) and the other end at 13 was only 38 feet. There didn't LOOK like a 28 ft disparity but I was only a school boy with an air band radio in those days.

[AlanM]

Thames Radar gives LCY traffic nothing....

Biggin Hill 21 arrivals get the threshold elevation (517'), and 03 arrivals get the aerodrome elevation (598') as it is a visual manouvre after a 21ILS.

Clear as mud then.......