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roach
21st Jan 2006, 15:29
Out of interest why is it that in the Uk ATC clear us for the localiser and only when established are we cleared for the ILS?
In Europe it is cleared for the ILS.
I remember something a few years back about the UK being different but why?

Idle curiosity!

HEATHROW DIRECTOR
21st Jan 2006, 16:18
It's been covered at great length, but here's the simple explanation.

Many moons ago the odd aircraft, when "cleared for the ILS" at Heathrow went straight down to around 1000 ft over Central London. In that area there are large numbers of other aircraft flying around under the ILS so the only answer was to change the procedures so that ATC controls the descent by instructing pilots to descend on the ILS once they have reported on the localiser, which is supposed to be interpreted as "fly the glidepath". It has worked for the last 35 years to my knowledge and does not present any problems so I guess they'll stick with it. Incidentally, in the days when the first incident occurred there was no SSR and the first Heathrow knew about it was when ATC at the Battersea Heliport rang up to ask why a Heathrow inbound was going through their circuit!!

Others will now embellish these details.........

roach
21st Jan 2006, 17:51
Thank you for the explanation. Here is the problem.....our A/C have a Nav or APPR option when cleared for the ILS, Nav will capture the loc but not descend, Appr will do both. At times of busy ATC I have been on the loc and unable to receive clearance to descend with the ILS which leaves the problem of throwing away the appr or waiting and capturing from above and we all know the right thing to do and we all know the practical. Fortunately these are very rare occurances but hopefully explains my interest!
Do ATC expect us to go down anyway on the G/S in the situation where we are unable to receive the clearance?

Regards.

aluminium persuader
21st Jan 2006, 21:49
The other possibility is that you're thinking of "cleared for the ILS approach..." as opposed to "turn left hdg xxx, Report loc established". The former is a procedural clearance which would clear you from present position to the initial approach fix, through the entry turn and out on the procedure to the ILS. The second would be given when as radar heading to intercept the localiser. There was a thread some while ago about this if you want to try a search.

ap:)

javelin
21st Jan 2006, 23:13
If radar have stated cleared to intercept the localiser with no other statement, TCAS shows no other traffic and then r/t clutter prevents a call before the g/s, I will descend and call descending asap. If however, radar has said intercept the localiser and maintain xxxx feet, then I won't.

chevvron
22nd Jan 2006, 12:27
This matter is to be discussed by the UK Phraseology Working Group at its next meeting.

catocontrol
22nd Jan 2006, 16:51
If radar have stated cleared to intercept the localiser with no other statement, TCAS shows no other traffic and then r/t clutter prevents a call before the g/s, I will descend and call descending asap. If however, radar has said intercept the localiser and maintain xxxx feet, then I won't.
Not good! Establish on the LLZ is the same thing as establish on a radial! It is not a decend clearance!

HEATHROW DIRECTOR
22nd Jan 2006, 17:02
Javelin. Catocontrol is right. If you use TCAS in lieu of ATC then you are asking for trouble. If ATC has not cleared you to descend it would be irresponsible to do so.

javelin
24th Jan 2006, 17:16
Well I ain't going round, that's for sure - it is an area that needs sorting. it appears to be a particular 'British' thing.

HEATHROW DIRECTOR
24th Jan 2006, 17:41
Let's get some commonsense into this thread. In 31 years of working as a Heathrow controller, during which I handled millions of flights I never saw nor heard of one which made a missed approach because the frequency was too busy to get descent clearance on the ILS.

Empty Cruise
24th Jan 2006, 19:27
HD,

I very much respect your experience - and still find the "two-step" procedure to take up time unnecessarily on busy freq's.

One guy not knowing how to fly an ILS approach from vectors sounds as an unfortunate experience, yes. But not something that in my ears sounds as a reasonable justification for doubling the amount of talk necessary to execute the single most used approach (98%) in the UK.

The flip side of this coin is - ATCOs on the continent have done it with one single clearance for years - and no-one over there have found it necessary to alter the procedures.?

Empty

radar707
24th Jan 2006, 20:06
I tend to find that "close the localiser from left/right, when established descend on the ILS" works wonders when I've got a busy frequency.

catocontrol
24th Jan 2006, 23:56
I tend to find that "close the localiser from left/right, when established descend on the ILS" works wonders when I've got a busy frequency.

But why?

"Cleared ILS approach 17"

is just as good as, and even better than:

ATC:"Intercept localizer runway 17"
A/C: "Established on the localizer, request decend"
ATC: "Decend on the glidepath"

notdavegorman
25th Jan 2006, 01:27
I have to say this "report localiser established" procedure in the UK isn't helpful from a pilot's perspective.

It adds significantly to the pilot-not-flying's workload, who's primary duty is to monitor the pilot-flying's actions, and having make an additional radio call to facilitate descent once the aircraft's autopilot is already locked on the localiser takes the pilot-not-flying's attention away from this. This problem is particularly apparent when the vectoring goes array and we intercept the localiser and glideslope almost simultaneously, we must get our "localiser established" in very quickly, otherwise we must contend with intercepting the glideslope from above, which can be problematic with a slow-witted autopilot and can lead to an unstable approach manually flown approach once it's recognised the dithering autopilot isn't going to do the job.

As other contributors have noted, the single stage clearance works just fine everywhere else in Europe.

I would suggest the following phraseology "Intercept ILS runway XX, not below 2000'".

This is an unambiguous clearance, as it's saying don't intercept the ILS below 2000', and to be ILS established, by definition one must be on the localiser!

BOAC
25th Jan 2006, 09:13
I never saw nor heard of one which made a missed approach because the frequency was too busy to get descent clearance on the ILS. - been close twice, HD and had to over-transmit on someone giving his inside leg measurement to ATC at the moment critique:)

I agree with the 'pilot' sentiment here - if there is no traffic to affect descent, why not clear it at the beginning? As said, it works fine elsewhere, so maybe we can get the procedures changed?

Preppy
26th Jan 2006, 10:51
FWIW, BALPA's Flight Safety Group have been in discussion with the UK authorities for a number of years over this particular issue.

I understand that the history of non-ICAO standard phraseology at LHR for an ILS descent clearance, followed the opening of LCY airport.

I have heard that NATS have recently proposed some R/T changes for LHR which are still not ICAO compliant. It is unlikely that any non ICAO proposal would be supported by BALPA.

The general feeling is that LHR should comply with all ICAO procedures.

HEATHROW DIRECTOR
26th Jan 2006, 11:08
There's very much more traffic than LCY by way of helicopters along the Thames and fixed wing SVFR traffic underneath at 1500 ft, the latter on easterlies too. I agree that standardisation would be great but changes to procedures are usually made with safety in mind even if they are "non-standard".

ukatco_535
26th Jan 2006, 11:25
I have to say this "report localiser established" procedure in the UK isn't helpful from a pilot's perspective.

It adds significantly to the pilot-not-flying's workload, who's primary duty......

I'm sorry, but one radio call in my book, is not a significant increase in the PNFs workload.... or at least if it is a significant increase (in percentage terms) it must mean he is doing hardly anything else - what is a significant increase? 50%??; therefore the pilot NF is only doing 2 other things??!!

The phraseology or procedure may not be great, but it is not a significant factor in workload.

757manipulator
26th Jan 2006, 11:35
Atco..mate its not the one radio call that adds to the workload, otherwise no one would be moaning about it.
Its the distraction of having to pick through a director freq when theres say 8 or 9 being vectored in sequence, a rapidly approaching G/S, then the PF is asking for config changes to commence the descent, all the while your trying as PNF to monitor and get a call in (rising stress levels..single point of focus etc etc) just when you dont need to and shouldnt have to IMHO.
Ive flown in many other parts of the world (the UK for the past 4 years) and Im in agreement with most on here, the Localiser then ILS rule is past its sell buy date. Perhaps its time for the procedure designers and ATC to sing from the same song sheet:ok:

Empty Cruise
26th Jan 2006, 13:49
HD,

AMS, MUC, FFM, HAM, LYS, GVA, BNC (to name a few) are all airports that have to cope with significant amounts of VFR traffic below their TMAs - and no-one there sees the need for the two-step clearance. Does anybody know of instances anywhere - apart from that unfortunate chap in the UK - where the one-step-approach has led to a reduced level of safety (or rather - where the one-step clearance has been misinterpreted in such an unfortunate way at the same time as said pilots procedural knowldge went out the window)?

Empty

notdavegorman
26th Jan 2006, 17:13
ukatco_535, it's not as simple as that. Let's say a 737 has just joined the localiser, the glideslope is often coming in rapidly, the PF will want to configure the aircraft with flaps and possibly gear too, otherwise an unstable approach might result. An example of the PNF's workload is just to make a flap selection, he first has to check they're below the placarded maximum speed for it, physically move the flap lever to the desired setting, check that the flap position indicator needle actually moves to the correct position, additionally, if the PF is flying manually, the PNF has to calculate in his head the correct bug speed for that setting (which is a function of our landing speed, at least with our SOPs), and then set it.

As well as this the PNF has to watch that the PF is flying the desired flightpath, at the desired speed, move various controls to their correct position for landing (arm the speedbrake, engine start switches to CONT etc), take the 'cabin secure' call from the cabin crew and read the landing checklist.

We are taught from our earliest flying lessons to AVIATE-NAVIGATE-COMMUNICATE, in that order, and having to call localiser established tends to push the latter into a more prominent position that it needs to be.

Anything to reduce the PNF's workload at this critical stage of flight can only be welcomed.

TATC
26th Jan 2006, 21:13
there is the phrase

"When established on the localiser, descend on the ILS" - a conditional descent clearance published in the UK Mats part one - which could solve this problem

chevvron
28th Jan 2006, 11:55
Like I said before, this subject will be discussed between SRG and ATS providers very soon.

Slaphead
28th Jan 2006, 12:54
From 1st of February there will be a six month trial of amended phraseology for use by the approach controllers for Heathrow, Gatwick, Stansted and Luton airports.

During periodsof high r/t loading, especially when controllers anticipate that pilots will intercept the ILS G/P before being able to report to ATC that they are established on the localiser the following phraseology may be used;

'callsign when established on the localiser, descend on the ILS'

notdavegorman
29th Jan 2006, 01:17
That's good, however one of the points I was trying to make was that it's not necessarily RT congestion that's the problem.

BOAC
29th Jan 2006, 10:58
Slaphead - good news! Do you have any details of the 'trial' - in particular how are airlines being notified and what (if any) will be the feedback process?

TATC
29th Jan 2006, 12:43
The phrase " when established on the localiser, descend on the ILS" has been in the UK MATS part 1 for a while, and has been in use on Heathrow Approach for a few years already

Regular Cappuccino
29th Jan 2006, 16:23
The phrase " when established on the localiser, descend on the ILS" has been in the UK MATS part 1 for a while, and has been in use on Heathrow Approach for a few years already

And at other ATC Units too - the problem seems to be that it's such a mouthful, compared to 'Cleared ILS' as used in Europe, which is probably why it's not used more often.:bored: