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". . . ready for descend"

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". . . ready for descend"

Old 22nd Jul 2007, 22:07
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Devil ". . . ready for descend"

One of the most frustrating things I experience daily is pilots asking for descend, descend instruction given, (often with having to vector traffic below out of the way) and they maintain level for another 4/5 minutes!!

Especially guilty are QTR, GFA, MAS & SAA drivers - would this perhaps be following company sop's?

OR is it just me?

JV
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Old 22nd Jul 2007, 22:35
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I agree.

If you are planning to start descend in 20 NM, but for some reason like to have the clearance now, please say so.

"ZZZXXX request descend in 20 miles."
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Old 23rd Jul 2007, 08:32
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A Britannia Pilot asked me for descent once and, as he had anticipated my next transmission, I was able to clear him down immeadiately. Minute or so later I noticed that he hadn't begun his descent so I asked him if he was leaving? He replied that he planned to start in another minute or so. It wasn't busy so I asked (politely) why had he requested descent when he wasn't ready?
The rueful reply was "the computer told us to" (years before Little Britain!!!).
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Old 23rd Jul 2007, 10:18
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One that bugs me is:

ATC: XXX123 descend flight level two five zero.

XXX123: 123, roger, re-cleared two five zero (sic), and ah do you want us to leave now?

ATC thinks but doesn't transmit: No, tomorrow morning will do fine

Hey guys & gals, when descent is given without any option in the clearance it means NOW. So don't waste my time asking
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Old 23rd Jul 2007, 10:39
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HT - this has been 'done to death' here before too - not all controllers are as good as you and often the clearance is actually an unspoken 'when ready', or there is some 'secretly' assumed descent rate or restriction in there somewhere. That is why we ask. I seem to recall the 'finding' of the previous incarnations was to use 'xxx Descend Now'?
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Old 23rd Jul 2007, 10:54
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HT - this has been 'done to death' here before too
BOAC, you're right of course, but this was meant as a gentle reminder. I do use "now" (although I still don't see why I should) and would you believe it, some (mainly those of two particular non-Brit nationalities I have to say) still ask me if I mean "now"

not all controllers are as good as you
Absolutely right, but I wonder if you meant that not all pilots are as good as me
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Old 23rd Jul 2007, 11:58
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Hey guys & gals, when descent is given without any option in the clearance it means NOW. So don't waste my time asking
All very well but on the majority of the times that I ask the question the answer is "no, when ready", descent clearance is often given 20-30 miles ahead of where it's needed and in that case I always ask (assuming r/t not too busy) if not given the option.
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Old 23rd Jul 2007, 12:56
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I haven't worked in Oz for a long time now, but from memory in the Australian MATS it says that any instruction to pilots must be followed within one minute of recieving the instruction. If that is the case then when an aircraft has asked for descent and descent has been given, at least in Oz, that aircraft must have started descent within one minute. It isn't unfortunately in the books here in the Middle East, so I am assuming it must just be an Oz only thing, but for me it's a great rule to have.

It happens here all the time and in our case I find Qatari and Gulf Air are the worst offenders of asking for descent and then maintaining for 4 or 5 minutes. You shouldn't have to say "descend now" in my opinion if the pilot has requested descent.
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Old 23rd Jul 2007, 14:15
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Except in the UK we don't use the word 'NOW'
From the UK MATS pt 1
5.7 Climb and Descent Clearances
5.7.1 Clearances to climb and descend are to include the expression 'flight level', 'altitude'
or 'height'. The word 'to' after the verb must be used when clearing an aircraft to an
altitude or height. It should not be used when a flight level is involved. The following
are examples of correct phraseology:
'Climb flight level 350'
'Descend flight level 240'
'Climb to altitude 2500 feet'
'Descend to height 1500 feet'
5.7.2 The expression 're-cleared' is not to be used.
I would have thought that any instruction to climb or descend is expect to be commenced on the completion of the message / reply.
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Old 23rd Jul 2007, 15:45
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tired-boy - yes, we know, and it was explored before, but the fact remains that as Max Angle says about 50/50 I guess it turns out to be 'when ready' when you ask. The suggestion was that the 'Now' would act as an imperative (excluding the "two particular non-Brit nationalities", of course). Does the MATS quote actually PRECLUDE using the word just because it is not there?

Perhaps pilots should actually request 'descent clearance (?when ready?) if it is simply a case of getting in a request when there is an R/T gap?

HT - my apologies - you confused me by apparently 'batting for the other side'
So don't waste my time asking
(in the BEST possible taste, of course)
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Old 23rd Jul 2007, 16:00
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Well let me amplify my response....

In the London TMA you will very rarely hear a 'when ready'.

Most instructions to climb or descend are to be followed when instructed to not when you (as a pilot are told to by the computer).

If coming into one of the holds you could expect to be given a 'level by' but we would still expect you descend at the min required (500fpm). OR ask if you can delay you descent for a specified distance.

From the AIP ENR 1.1.3
2.3 Minimum Rates of Climb and Descent

2.3.1 In order to ensure that controllers can accurately predict flight profiles to maintain standard vertical separation between aircraft, pilots of aircraft commencing a climb or descent in accordance with an ATC Clearance should inform the controller if they anticipate that their rate of climb or descent during the level change will be less than 500 ft per minute, or if at any time during such a climb or descent their vertical speed is, in fact, less than 500 ft per minute.

2.3.2 This requirement applies to both the en-route phase of flight and to terminal holding above Transition Altitude.

Note: This is not a prohibition on the use of rates of climb or descent of less than 500 ft per minute where necessary to comply with other operating requirements.
...often the clearance is actually an unspoken 'when ready', or there is some 'secretly' assumed descent rate or restriction in there somewhere.
so to from what you said i have shown you it is not an unspoken when ready and the secretly assumed descent rate is in the book.
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Old 23rd Jul 2007, 16:13
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t-f - agreed, but they do let us out of the London TMA occasionally. Are you saying that crews are doing this IN THE TMA? I'd be suprised if anyone was 'awaiting' a computer generated descent in the London TMA.

Amongst many, frequent occurrences for me north-bound on the 'Welsh' airway when an early 'descend' call from ATC turns out to be a 'level-by'. This has also been well-aired elsewhere on PPRuNe, plus the comment made that Maastricht are generally good in making it clear and/or giving a required rate of descent.
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Old 23rd Jul 2007, 17:41
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On the same kind of topic... why is it when over Spain/France and requesting descent from cruise level, the controller will always say "for descent, contact xxxxx".

Surely the controllers have some idea where our ToD point is so could transfer us before us calling for descent and thus missing out ToD point? Or have I got it totally wrong?

Any suggestions most welcome!

M330
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Old 23rd Jul 2007, 20:00
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Lightbulb

"...plus the comment made that Maastricht are generally good in making it clear and/or giving a required rate of descent."

I remember at Maastricht once giving a RoD - for traffic as one does - and noticed that the pilot wasn't complying. After questioning him he replied rather irritatedly that it was his intention to give me the required RoD as an average!!

Ranks as high as being told once; "Turning left 20 degrees to avoid a RA!!!"

JV
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Old 24th Jul 2007, 22:33
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I feel sure there used to be a requirement that when given an instruction to descend, you had to descend at no less than 500 ft a minute. This might have changed, but if it hasn't, anyone given a descent clearance (without the when ready), should immediatley start a descent at no less than 500 fpm. Waiting a minute or two before descending might ellicit an MOR. A lot of lesser things do.
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Old 25th Jul 2007, 16:01
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I think we need to inject a bit of common sense in our attitude to "clearance" versus "instruction". The division between the two has long since eroded, and is a fine distinction left over from a bygone age of procedural controller assisted by radar controller, in the UK at least.
Remember that we deal with aircrew from all over the world, and that some UK aircraft operate in ATC environments all over the world. Rather than refer to a parochial document----which would be completely valid----we should strive to accomodate all our customers by injecting clarity where there may be room for doubt or misinterpretation.
Monarch A330: you may be working a high level sector to protect a low level sector workload; many Centres use a system of vertical or layer sectorisation. We don't always know your TOD, you may be a flutter-down feather type [the BUS] or a Boeing/exec jet dive bomber.....unfortunately some of our procedures are a one-size-fits-all......but those procedures move an incredible amount of traffic almost beyond the dreams of the initial system designers.
Just Visiting: you have identified the operators who make these requests. You could adapt your method of control to accomodate them and pre-plan your technique to suit. These people pay our wages. On the other hand it is unreasonable for an a pilot to expect a large section of airspace to be..in effect..reserved, if it is a busy environment. Alternatives are to issue a very minor level change and wait for commencement of descent......or just refuse the request until the aircraft is actually ready to commence....if there is a genuine traffic reason.
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Old 25th Jul 2007, 16:46
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BOAC, interestingly - well sort of - the descent/climb rate techniques you mention are not taught at Hurn, or at least they weren't on my incarnation of the course. My first experience was when I took a fam flight to EDDF during the course and our German counterparts specified rates. During live training it emerged as a viable and legitimate technique, but that's probably why it's not heard so much in the UK.

The scenario you describe on the welsh airway isn't clear enough for me to make many assumptions, other than that you are probably descending into the Manchester TMA? I certainly don't wish to insult your intelligence (7000+ posts and moderator status suggest an experienced operator!!) and you are probably aware that the 'West End' was resectorised just over a year ago. If my assumptions so far are correct, then you'll be well used to something like FL330 Exmor - Manch TMA are capped out of BCN high-level (FL335+). Unfortunately we are waiting for an acceptance from the BCN sector so that level may change dependent on other traffic. If descent is late and unreasonable I believe that it's our fault and ours to sort, without you having to get all dirty/spill the drinks!! (We are taught mental maths re: minimum descent rates if not specifying rates!!) Hopefully in your scenario the initial call was to start initial descent through east/west traffic so that the late descent doesn't arrive at exmor, the subsequent 'level by' once the next sector confirms the acceptance level.

I'm not trying to teach anyone to suck eggs, hopefully it's useful - i'm sure similar scenarios happen all over the place.

Referring to the initial point of the thread, the 'welsh' airway/BCN scenario also serves up a case study (again replicated everywhere i'm sure!) At BCN Manch TMA and EGLL (eastbound) arrivals are capped FL 330 or below, putting all a/c on similar profiles regarding standing agreements later. The wind will often dictate who gets into BCN lower (eg. strong southerly, GP below LL, etc.) If a pilot requests descent and the opportunity is there for an ATCO to facilitate that, then descent is given (hopefully!! ). Now I normally say descend NOW if i'm the instigator but I have nearly been caught out in this scenario as I decide to get the higher inbound below the other a/c (also soon to be descending). I expected the pilot to descend after requesting it, not float along until in confliction with the other a/c before commencing descent! So, personal lesson learnt there! Clearly descent wouldn't be given if it is too late to 'swap' the relative positions at the crossing point. This is one of many potential scenarios really

Anyway, enough waffling, I understand the initial poster's frustration but I try and use common sense where bureaucracy fails! Why tempt fate? Hope the scenarios shed some light to anyone it helps as to the ATCO viewpoint.

WW
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Old 25th Jul 2007, 18:45
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Thanks WW - thanks also to one of your ATC colleagues I have sight of the whole sectorisation/level thing, and the 'Welsh' story was in some way anecdotal to reinforce the common occurrence of being given descent WELL before the 'economic' point (this was indeed inbound LBA) and when asked turned out to be 'when ready to be xxx at yyy before zzz' which was somewhat later. This is not to say that a large proportion of you guys and girls do not have a 'feel' for the profiles.

I feel partly guilty in hijacking the thread away from the origin but it was really to try and explain to HT why we were prone to ask the question.

Re the 'rate' descent, maybe it needs to be looked at in the UK? Do Maas have different/better equipment that allows them to accurately predict required separation levels so a rate can be issued? I would bet a to a pinch of horse whatsit that in Maas airspace a large proportion of a/c ACTUALLY begin descent when cleared, if given a rate in the clearance. It always 'focusses' my mind and sub-consciously I must think - 'he/she has worked it out and wants that so it must be now' - useful psychology maybe?
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Old 26th Jul 2007, 10:03
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I understand your point entirely - I think and would hope that the majority of my colleagues are well aware that most of our standing agreements and intermediate en-route level restrictions are far from the preferred profile of most aircraft. Unfortunately these are the rules we have to play by, reducing overall complexity by removing certain traffic types from a sector and thus increasing overall capacity.

LBA in particular is very restrictive inbound, you are effectively forced to follow the same profile that manchester and even liverpool inbounds have to follow. It also has the frustrating effect (for you I suspect) that you have probably found yourself speed restricted against such liverpool/manch traffic, so that we can get you through the same point ( 10dme Monty @ 200) at the same level!!

A good point you make about MAAS, a given rate does imply a descend NOW. I was quite surprised when I discovered quite a major technique that I hadn't been taught. There's probably a reason for it to which i'm not privy!! MAAS may have kit to help them decide - I don't know to be honest - although I imagine it would be possible to do simply mentally (what do I need you at in 5 mins, etc, etc, calculate rate).

WW
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Old 26th Jul 2007, 10:59
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WW

Para 1 - thanks to your afore-mentioned colleague the 'gates' are no longer a secret to me or my airline ops , so my fuel planning has been adjusted in most cases. There is another thread pointing out how these' early' descents - if unplanned - can be critical to the much-pared fuel reserves we are now asked to carry. My point is the lack of 'clarity' in a 'descend' call which should have been 'when ready to be xxx' but is just issued as 'descend FLxxx'.

Para 2 - that's it!! 10 before Monty - the brain cell is dying........... No, speed control is not a problem and I don't think I've actually had any 'unexpected' in that sector.

Para 3 - would there be a 'career threatening' implication for UK controllers if they tried the 'rate' call?
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