You want us to descend now?
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I am quite happy as a ATCO to say its ATC providing pilots with a service, however, what a crutial service it is.
On a slightly different edge, and one thats been here before, is including the 'expect FL*** by ***' I have had far too many experiences to now have to reinforce this to some, but time and again have to clarify its only an 'expect ' level. We need this read back on the tapes, otherwise we are in deep sh!te should a level bust occur. When levels are known by me to be published in the STAR charts, I feel the whole transmission to be a total waste of time, but when they aren't reitterated by me, at least half check what to expect. Its a case of either "why print them" or "why have to reitterate them".
So to all pilots out there, do you expect to be given the restriction eventually and ALWAYS plan descent for them, or are you one of those that will only get there if told to do so at top of descent??????
On a slightly different edge, and one thats been here before, is including the 'expect FL*** by ***' I have had far too many experiences to now have to reinforce this to some, but time and again have to clarify its only an 'expect ' level. We need this read back on the tapes, otherwise we are in deep sh!te should a level bust occur. When levels are known by me to be published in the STAR charts, I feel the whole transmission to be a total waste of time, but when they aren't reitterated by me, at least half check what to expect. Its a case of either "why print them" or "why have to reitterate them".
So to all pilots out there, do you expect to be given the restriction eventually and ALWAYS plan descent for them, or are you one of those that will only get there if told to do so at top of descent??????
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Loki - because we fly in lots of different ATC sectors we often get 'descend FLxxx' which on query turns out to be 'when ready' or 'at pilot's discretion'. Not everyone is like you and says 'when ready'. This probably makes us wary!
BTW Any chance of the CAP 'guidance'?
5miles- all modern FMCs can (should) be programmed with the published altitude restrictions. There is NO excuse! I agree with you, it is a pain to have to read back 'level 75 before MID' when you and I know it is in the STAR!
BTW Any chance of the CAP 'guidance'?
5miles- all modern FMCs can (should) be programmed with the published altitude restrictions. There is NO excuse! I agree with you, it is a pain to have to read back 'level 75 before MID' when you and I know it is in the STAR!
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I find that 'descend now' doesn't use nearly as much R/T time as responding to the query "Is that descend now, or pilot's discretion, London?"
One thing I've noticed, though. Why do some crews request descent, then not leave the level for several minutes? Seems to be a charter airline peculiarity.
Also, in the recent months of excessive delays, level restrictions, etc etc, I've found flight crews to be tolerant, friendly and uncomplaining.
So to pilots using UK airspace these days, thanks.
One thing I've noticed, though. Why do some crews request descent, then not leave the level for several minutes? Seems to be a charter airline peculiarity.
Also, in the recent months of excessive delays, level restrictions, etc etc, I've found flight crews to be tolerant, friendly and uncomplaining.
So to pilots using UK airspace these days, thanks.
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Been away for awhile <G>....
Over here, one reason you don't hear to many folks say descend now is because that isn't the proper phraseology. Descend and maintain means descend now... What you will usually hear over here is either descend at pilots discresion or cross XXX at and maintain... Do we sometimes just say descend and maintain when we don't need you to go down right now? Sure, but that was already explained rather well by AF-1.
As to the direct thing... We have been briefed by the companies that they have spent quite a few bits of money investing in flight planning software that looks into the most beneficial route of flight ( unless of course we have a traffic flow management route in effect due to weather ). When we up and give someone direct that then takes them out of the most beneficial wind component, the pilot flying is happy, but then the company is unhappy and sometimes actually makes a call to either us, or an acars to the flight deck when the dispatcher figures out they aren't on the flight planned route and has them get back on it. Thus making the workload even more for someone else a hundred miles away.
regards
Over here, one reason you don't hear to many folks say descend now is because that isn't the proper phraseology. Descend and maintain means descend now... What you will usually hear over here is either descend at pilots discresion or cross XXX at and maintain... Do we sometimes just say descend and maintain when we don't need you to go down right now? Sure, but that was already explained rather well by AF-1.
As to the direct thing... We have been briefed by the companies that they have spent quite a few bits of money investing in flight planning software that looks into the most beneficial route of flight ( unless of course we have a traffic flow management route in effect due to weather ). When we up and give someone direct that then takes them out of the most beneficial wind component, the pilot flying is happy, but then the company is unhappy and sometimes actually makes a call to either us, or an acars to the flight deck when the dispatcher figures out they aren't on the flight planned route and has them get back on it. Thus making the workload even more for someone else a hundred miles away.
regards
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Scott, you're right that 'descend now' isn't correct phraseology, but, hey, if it works...
Out of interest, do you ever have problems with the term 'maintain'? If you clear an aircraft to a level without using that word, what will he do when he gets there?
In the UK, maintain is generally used to advise a pilot not to expect continuous climb, and caution therefore is used when talking to American pilots.
Hope things are sweet in Tx!
Out of interest, do you ever have problems with the term 'maintain'? If you clear an aircraft to a level without using that word, what will he do when he gets there?
In the UK, maintain is generally used to advise a pilot not to expect continuous climb, and caution therefore is used when talking to American pilots.
Hope things are sweet in Tx!
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5milesbaby. Interesting question. Ay my home base the arrivals all have several descent restrictions but I have never once had to comply with them all. In fact I have never seen most of them imposed. There is usually only one of the restrictions which applies and from local knowlage thats what I "plan"my descent on. Several of the arrivals have very "Draggy" restrictions which force an early descent but are only enforced in busy periods or when there is a full moon or something. Some have "Secret" restrictions which force a screaming jeesus descent to satisfy if not planned on. Confused? You should be.
While we are on the subject of wasted atc transmission time ,why do ATC insist on all these (unpublished and secret) "Twenty before Trents" and "Ten before Monty" things when the FIR is festooned with waypoints that nobody EVER uses?
Question-"Is that at our discretion?"
Answer-"Affirm" or "Negative" That wasn't really too difficult or long winded was it?
While we are on the subject of wasted atc transmission time ,why do ATC insist on all these (unpublished and secret) "Twenty before Trents" and "Ten before Monty" things when the FIR is festooned with waypoints that nobody EVER uses?
Question-"Is that at our discretion?"
Answer-"Affirm" or "Negative" That wasn't really too difficult or long winded was it?
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The maintain part is just another thing in our verbage in our ATC bible... <shrug> I understand that if all is done right, you are going to maintain that altitude <G>...
regards
regards
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Homer, I can answer one of your questions. FL200 lvl 10nm b4 Monty is the Standing Agreement between London Sector 5 (Brecon) and Manchester West Sector. Manchester West have to then get you below FL195 BY Monty, otherwise you enter another Sectors airspace (S29). It keeps everyone happy the way its done, and as the STAR chart starts at Monty, the restriction to expect before it aint written on. However, in my mind and many others, it should be for the whole descent to keep everyone in the picture.
If people feel having them all on the plates is useful, how about getting together to get them changed??? There must be a division in NATS that could help out, although new centre = new division = new name !!!!!!!!
If people feel having them all on the plates is useful, how about getting together to get them changed??? There must be a division in NATS that could help out, although new centre = new division = new name !!!!!!!!
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Come on - someone must have the ATC bible in the attic! What DOES 'descend' mean in the UK? Can it be expanded to 'now'/'when ready'/'pilots' discretion'/etc within the CAP terminology?
Knowing this will help us IN THE UK at least - we will still have to juggle the foreign 'balls' though, but maybe we can take a bit of steam out of the kettle here?
Any gurus know from where Jepps and Thales get their info for airfield plates?
Knowing this will help us IN THE UK at least - we will still have to juggle the foreign 'balls' though, but maybe we can take a bit of steam out of the kettle here?
Any gurus know from where Jepps and Thales get their info for airfield plates?
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OK - how about the ATC PPruners spread the word?
How about we trial, say ?a couple of months?, using the differentiators 'now' and 'when ready' - with any 'gates' you want us to achieve - for descent clearances in the UK? (Hoping your managers don't throw a 'wobbly' of course!).
Let's have a 'debrief' on how it went, here, then?
Over.
How about we trial, say ?a couple of months?, using the differentiators 'now' and 'when ready' - with any 'gates' you want us to achieve - for descent clearances in the UK? (Hoping your managers don't throw a 'wobbly' of course!).
Let's have a 'debrief' on how it went, here, then?
Over.
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I'm afraid that I am struggling to work out what it is about the word "Descend" that people don't understand. It is an instruction, a command even. It doesn't mean "when you feel like it" or "when your on board computer feels like it" or when you've finished your coffee and the crossword. It means "DO IT". NOW would be nice. After all, if I say "turn left heading 290, closing from the left report established", pilots don't ask if they should do it now or at their discretion. Why should "Descend" be any different?
Rightly or wrongly I teach trainee controllers that when they instruct an aircraft to descend, it will, plus or minus the "wake-up-was-that-for-us" scenario and the inevitable short delay actually getting the thing to come down. But to all intents and purposes read "immediately".
There is nothing (that's ZERO) in the MATS Pt1 about "Descend when ready" or any equivalent. Descend IMMEDIATELY (my caps) is to be used only to resolve an urgent situation. The only bit that looks remotely useful is "Descend to reach (level) at/by (time/significant point).
For the curious or bored the MATS can be read at
http://www.caa.co.uk/docs/33/CAP493__Part1.pdf
then go to Section E (Attach) Page 3 and look for the Climbing & Descending bit.
Controllers do appreciate the economics of commercial aircraft operation and try to take that into account BUT there has to be a trade off with other requirements such as other traffic, sequencing, standing agreements with other units ad nauseum. With the best will in the world your ideal descent profile is going to be bent a bit. Don't add to it by causing controllers to mutter "Of course I mean bloody now!"
Rightly or wrongly I teach trainee controllers that when they instruct an aircraft to descend, it will, plus or minus the "wake-up-was-that-for-us" scenario and the inevitable short delay actually getting the thing to come down. But to all intents and purposes read "immediately".
There is nothing (that's ZERO) in the MATS Pt1 about "Descend when ready" or any equivalent. Descend IMMEDIATELY (my caps) is to be used only to resolve an urgent situation. The only bit that looks remotely useful is "Descend to reach (level) at/by (time/significant point).
For the curious or bored the MATS can be read at
http://www.caa.co.uk/docs/33/CAP493__Part1.pdf
then go to Section E (Attach) Page 3 and look for the Climbing & Descending bit.
Controllers do appreciate the economics of commercial aircraft operation and try to take that into account BUT there has to be a trade off with other requirements such as other traffic, sequencing, standing agreements with other units ad nauseum. With the best will in the world your ideal descent profile is going to be bent a bit. Don't add to it by causing controllers to mutter "Of course I mean bloody now!"
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From this thread, it seems that many ATCOs are uncertain of the method of navigating, vertically, in modern (FMS-equipped) aircraft. In a couple of weeks' time, I would be willing to start an 'FMS Q and A' thread, and to do my best to answer any queries ATCOs have about these matters. Would this be a help? Are there any other experienced jet pilots out there willing to pitch in with answers, too? (I'm currently on Boeings - and mahogany bombers, so not a sharp as once was - but with previous 'bus technology experience. Is there a currect 'bus driver who might give that persepective?)
Or am I miles off?
Or am I miles off?
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Well, Bern has made his point fairly clearly! All we flight crew need to do now is to clarify the rest of the world's R/T procedures outside Bern's sector. I shall now TRY to remember not to ask 'is that when.............." - in the UK.
Next 'Q': Is 500'/min an acceptable minimun rate if we are not actually ready for descent?
NS - happy to help (Boeing again) if you need it.
Next 'Q': Is 500'/min an acceptable minimun rate if we are not actually ready for descent?
NS - happy to help (Boeing again) if you need it.
Last edited by BOAC; 13th Aug 2002 at 19:17.
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Sorry to drag you all back to the direct thing but Scott's comments rang another bell. He's not the only one to get in trouble for offering direct routeings - some of us actually have direct (written) instructions FORBIDDING us from offering them (apparrently, as Scott said, at the airlines' request) and risk getting into all kinds of smelly stuff for doing the sensible thing and making all our lives' easier. Funny , I thought ATC was all about providing a service!!!
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5milesbaby
You've actually raised another point that while (briefly) blip driving at LATCC didn't quite get resolved. "xxx123 Descend FL70 to be level 10 miles before DAYNE/TNT etc."
Now......two schools of thought here
1. Descend at standard expected rate (1500 fpm) which could level out well before the 10 mile minimum, ie level out early
2.Descend at a computed rate to achieve level exactly at 10 miles before which could be a descent rate of anything from 500 - 2500 fpm.
There could be potential conflicts with either of these.
Another option which was dismissed was achieving a 1500 fpm descent to achieve level exactly 10 miles before, which meant delaying the start of descent.
We were told categorically that "Descend" meant now. "At your discretion" whenever, there wasn't anything in between. Why should there be? You don't qualify "Turn" "Climb" so why "Descend"?
You've actually raised another point that while (briefly) blip driving at LATCC didn't quite get resolved. "xxx123 Descend FL70 to be level 10 miles before DAYNE/TNT etc."
Now......two schools of thought here
1. Descend at standard expected rate (1500 fpm) which could level out well before the 10 mile minimum, ie level out early
2.Descend at a computed rate to achieve level exactly at 10 miles before which could be a descent rate of anything from 500 - 2500 fpm.
There could be potential conflicts with either of these.
Another option which was dismissed was achieving a 1500 fpm descent to achieve level exactly 10 miles before, which meant delaying the start of descent.
We were told categorically that "Descend" meant now. "At your discretion" whenever, there wasn't anything in between. Why should there be? You don't qualify "Turn" "Climb" so why "Descend"?
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Hi Jane,
See me earlier reply.
'Turn' - by the very nature of vectoring, is given at an appropriate time, and does not delay our progress (unless it's one of those French 60degree jobbies to allow Air France to carry on without changing course).
'Climb' - well, we're not going to say no! You will know that our engines are most efficient at altitude, so we always want to be as high as we can (weight plays a small part here, as may very strong winds).
'Descend' - equivalent to 'get there later and burn more fuel'. In the circumstances you describe, we'll either use Vertical Speed mode to achieve 500fpm until on the desired profile to just make the restriction,followed by idle power descent, or use VNAV in 'Capture' mode, which will give a 1000fpm descent until on the profile, then ide power descent, or use level change/open descent to give the least efficient idle power descent to the cleared level. Most pilots will not do this last one. 1500fpm is not stated anywhere as a standard rate of descent.
See me earlier reply.
'Turn' - by the very nature of vectoring, is given at an appropriate time, and does not delay our progress (unless it's one of those French 60degree jobbies to allow Air France to carry on without changing course).
'Climb' - well, we're not going to say no! You will know that our engines are most efficient at altitude, so we always want to be as high as we can (weight plays a small part here, as may very strong winds).
'Descend' - equivalent to 'get there later and burn more fuel'. In the circumstances you describe, we'll either use Vertical Speed mode to achieve 500fpm until on the desired profile to just make the restriction,followed by idle power descent, or use VNAV in 'Capture' mode, which will give a 1000fpm descent until on the profile, then ide power descent, or use level change/open descent to give the least efficient idle power descent to the cleared level. Most pilots will not do this last one. 1500fpm is not stated anywhere as a standard rate of descent.
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By forcing a/c to leave a level earlier than they want, I understand that the initial rate of descent won't be that high. However, at least they are going down. Being told to leave early means that normally something is in the way, or the one in front is descending and we want you in similar levels to speed effectively. Expediting an a/c already in the descent gives a more immediate resolution than one told 'start descent now, expedite' due to the delay in initial downward movement. In the ideal world, (like the sims) getting an a/c to leave and giving the restriction, I would like to see the rate of descent adjusted to give a constant rate of descent to hit the restriction, but I know in the real world this'll never happen.
I've started on a couple of my sectors now to give intermediate restrictions to ensure that an a/c is at the level I want it to be at to able separation in the awkward corners. It works well and creates none of the problems in this thread.
I've started on a couple of my sectors now to give intermediate restrictions to ensure that an a/c is at the level I want it to be at to able separation in the awkward corners. It works well and creates none of the problems in this thread.
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Remember the MATS Part 1 is NOT the sole document which ATC have to abide by. We also have the AIP and the CAP 413. Seems black and white to me from those other documents what to expect. But then I always was a simpleton and liked the easy way out in life 
Do we really need to reinvent the wheel ???
CAP413
Chapter 3 Page 3 Paragraph 2.3.4
Pilots are expected to comply with ATC Instructions as soon as they are issued. However, when a climb/descent is left to the discretion of the pilot, the words 'when ready' shall be used; in these circumstances the pilot will report 'leaving' his present level. Should pilots be instructed to report leaving a level, they should inform ATC that they have left an assigned level only when the aircrafts altimeter indicates that the aircraft has actually departed from that level and is maintaining a positive rate of climb or descent, in accordance with published procedures.
UK AIP
ENR 1-1-3-1 Paragraph 2.2
2.2.1 In order to ensure that controllers can accurately predict flight profiles to maintain standard vertical separation between aircraft, pilots of aircraft commencing climb or descent in accordance with an ATC clearance should inform the controller if they anticipate their rate of climb or descent during the level change will be less than 500 feet per minute, or if at any time during such a climb or descent their vertical speed is, in fact, less than 500 feet per minute.
2.2.2 This requirement applies to both the en route phase of flight and to terminal holding above the Transition Altitude.
Note: This is not a prohibition on the use of rates of climb or descent of less than 500 feet per minute where necessary to comply with other operating procedures.
Chapter 3 Page 3 Paragraph 2.3.4
Pilots are expected to comply with ATC Instructions as soon as they are issued. However, when a climb/descent is left to the discretion of the pilot, the words 'when ready' shall be used; in these circumstances the pilot will report 'leaving' his present level. Should pilots be instructed to report leaving a level, they should inform ATC that they have left an assigned level only when the aircrafts altimeter indicates that the aircraft has actually departed from that level and is maintaining a positive rate of climb or descent, in accordance with published procedures.
UK AIP
ENR 1-1-3-1 Paragraph 2.2
2.2.1 In order to ensure that controllers can accurately predict flight profiles to maintain standard vertical separation between aircraft, pilots of aircraft commencing climb or descent in accordance with an ATC clearance should inform the controller if they anticipate their rate of climb or descent during the level change will be less than 500 feet per minute, or if at any time during such a climb or descent their vertical speed is, in fact, less than 500 feet per minute.
2.2.2 This requirement applies to both the en route phase of flight and to terminal holding above the Transition Altitude.
Note: This is not a prohibition on the use of rates of climb or descent of less than 500 feet per minute where necessary to comply with other operating procedures.
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Don't know if it was as a result of this thread, but inbound this AM on a Willo3B to LGW, and a very clear 'Descend Now' from the controller. Great!
It may not be 'kosher', but by 'eck, it is clear! Is there really a problem with this?
"Pilots are expected to comply with ATC Instructions as soon as they are issued. However, when a climb/descent is left to the discretion of the pilot, the words 'when ready' shall be used; in these circumstances the pilot will report 'leaving' his present level. "
I think, PPR, most of us appreciate this, but as we have tried to explain, this is an international forum, we fly internationally, so it is not just a UK thing. Not normally a problem for UK pilots in UK airspace as we generally know and are ready for all the arcane descent restrictions, but maybe for visting crews.......?
It may not be 'kosher', but by 'eck, it is clear! Is there really a problem with this?
"Pilots are expected to comply with ATC Instructions as soon as they are issued. However, when a climb/descent is left to the discretion of the pilot, the words 'when ready' shall be used; in these circumstances the pilot will report 'leaving' his present level. "
I think, PPR, most of us appreciate this, but as we have tried to explain, this is an international forum, we fly internationally, so it is not just a UK thing. Not normally a problem for UK pilots in UK airspace as we generally know and are ready for all the arcane descent restrictions, but maybe for visting crews.......?