Descent clearance
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Descent clearance
I'm sure this has been asked before but I keep getting conflicting opinions from pilot colleagues.
Say I'm at FL380 with 20 miles to run to my descent point when I get the following instruction: "Descend FL290, 2000fpm or greater". So this takes me below my ideal descent profile.
As I'm passing FL320, I then receive "Descend FL220" from the same controller. Now, I understand this is a new clearance which replaces the old clearance, so I can descend at, say, 1000fpm, to get back on my profile.
But some would say you should maintain 2000fpm until FL290. Who's correct, and is there a written reference?
Many thanks!
Say I'm at FL380 with 20 miles to run to my descent point when I get the following instruction: "Descend FL290, 2000fpm or greater". So this takes me below my ideal descent profile.
As I'm passing FL320, I then receive "Descend FL220" from the same controller. Now, I understand this is a new clearance which replaces the old clearance, so I can descend at, say, 1000fpm, to get back on my profile.
But some would say you should maintain 2000fpm until FL290. Who's correct, and is there a written reference?
Many thanks!
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Any clearance supercedes the last. It's somewhere in the UK AIP.
In your example, the controller needs to reiterate the rate, otherwise it's all yours.
Of course, you could always ask the controller if in doubt......
In your example, the controller needs to reiterate the rate, otherwise it's all yours.
Of course, you could always ask the controller if in doubt......
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To be totally pedantic, each controller or each clearance must indicate whether there is a constraint.
If you are cleared 270 by LIFFY ( my personal Nemesis ) and as you approach, they throw you to MAN who say descend 190, you do not have to make 270 by LIFFY and can maintain 500 f.pm. until you regain your profile, provided the MAN controller does not re iterate the constraint.
Now, this is not a flame issue with ATC, it is a really pissed off attitude to the people higher up who issue block standing agreements without concern to our standard profiles and normal descent rates.
It is high time the front end and the ground end got together more and achieved some better BSA's
If you are cleared 270 by LIFFY ( my personal Nemesis ) and as you approach, they throw you to MAN who say descend 190, you do not have to make 270 by LIFFY and can maintain 500 f.pm. until you regain your profile, provided the MAN controller does not re iterate the constraint.
Now, this is not a flame issue with ATC, it is a really pissed off attitude to the people higher up who issue block standing agreements without concern to our standard profiles and normal descent rates.
It is high time the front end and the ground end got together more and achieved some better BSA's
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Originally Posted by CamelhAir
Any clearance supercedes the last. It's somewhere in the UK AIP.
I don't know where in the UKAIP it appears but it is confirmed here, at the top of page 4.
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I don't recall receiving the 2000'/min type clearances in the UK very often so I don't see how the UKAIP will help. This is a speciality of Germany and more recently Maastricht. Have you had this clearance in the UK? I can only remember it once towards Biggin when asked for 270kts, 2000'/min and level by Tiger.
Anyway as far as the general point goes this has been done before and the answer is that if the controller doesn't repeat the restriction of ,say, be level by Saber then the restriction no longer holds. That is the letter of the manual as I understand it. However, I have read here that while that may be technically correct it might actually be useful just to comply with it anyway in case the controller has not pedantically stuck to every T crossing and I dotting routine required.
Anyway as far as the general point goes this has been done before and the answer is that if the controller doesn't repeat the restriction of ,say, be level by Saber then the restriction no longer holds. That is the letter of the manual as I understand it. However, I have read here that while that may be technically correct it might actually be useful just to comply with it anyway in case the controller has not pedantically stuck to every T crossing and I dotting routine required.
However, I have read here that while that may be technically correct it might actually be useful just to comply with it anyway in case the controller has not pedantically stuck to every T crossing and I dotting routine required.
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Javelin, if you do what you say at LIFFY then you could end up in the brown stuff.
The standing agreement issue has been talked about loads before on other threads. Although they are restrictive on you guys, they are there to facilitate the flow of the traffic to aid everybody.
In your example, the ATCO at Shannon Centre has told you to descend to FL 270 by LIFFY. This gets you beneath Lakes airspace and into Manchester Area Centre's IOM sector. The Shannon ATCO will monitor your rate of descent & if it looks like you are going to make the S.A then he will transfer you to the IOM ATCO.
Now here is the tasty bit.
The IOM ATCO descends you to FL190, therefore the restriction that the previous ATCO gave you still applies as it is not that ATCO that has given you a new clearance. SO the clearance of FL270 at LIFFY still applies. If you do not meet the standing agreement then this causes a lot of co-ordination betwwen sectors as you will be entering someones airspace that you are not permitted to be in.
Best scenario - the ATCOs co-ordinate your descent if it is safe to do so.
Middle scenario - you may have to make an orbit in your present position to get the height off to make the standing agreement.
Worst scenario - there is a Mil Crosser 10nm east of LIFFY co-ordinated thru at FL280, because you should be at FL270 by LIFFY. Could be messy.
If in doubt, and the same goes for anything else, ask the ATCO.
The standing agreement issue has been talked about loads before on other threads. Although they are restrictive on you guys, they are there to facilitate the flow of the traffic to aid everybody.
In your example, the ATCO at Shannon Centre has told you to descend to FL 270 by LIFFY. This gets you beneath Lakes airspace and into Manchester Area Centre's IOM sector. The Shannon ATCO will monitor your rate of descent & if it looks like you are going to make the S.A then he will transfer you to the IOM ATCO.
Now here is the tasty bit.
The IOM ATCO descends you to FL190, therefore the restriction that the previous ATCO gave you still applies as it is not that ATCO that has given you a new clearance. SO the clearance of FL270 at LIFFY still applies. If you do not meet the standing agreement then this causes a lot of co-ordination betwwen sectors as you will be entering someones airspace that you are not permitted to be in.
Best scenario - the ATCOs co-ordinate your descent if it is safe to do so.
Middle scenario - you may have to make an orbit in your present position to get the height off to make the standing agreement.
Worst scenario - there is a Mil Crosser 10nm east of LIFFY co-ordinated thru at FL280, because you should be at FL270 by LIFFY. Could be messy.
If in doubt, and the same goes for anything else, ask the ATCO.
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DTY/LKS - while I am in full agreement with your sentiments and advice to 'check' if in doubt, it looks as if SRG and you are in disagreement. From the link given above (p4)
Maybe you need to raise this issue formally? If I recall all the previous threads correctly on this they all agreed with the SRG.
Similarly, if the original clearance included a restriction, e.g. ‘cross XYZ FL180 or below' then the issue of a revised clearance automatically cancels the earlier restriction, unless it is reiterated with the revised clearance.
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The IOM ATCO descends you to FL190, therefore the restriction that the previous ATCO gave you still applies as it is not that ATCO that has given you a new clearance. SO the clearance of FL270 at LIFFY still applies. If you do not meet the standing agreement then this causes a lot of co-ordination betwwen sectors as you will be entering someones airspace that you are not permitted to be in.
There is no room for interpretation really. A new clearance will cancel any restriction in that part of the aircraft's profile (by that I mean a horizontal instruction won't cancel a vertical restriction and vice versa).
Otherwise there is no cast iron guarantee that the pilots will all do the same thing and no guarantee that an ATCO won't end up with egg on his face.
If you (as an ATCO) need a previous restriction adhered to then you either have to restate it, or else give an instruction such that the aircraft's minimum performance in accordance with the rules (500fpm climb/descent rate) will meet the restriction anyway.
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no written referance, just life experience:
we get these v/s clearances a lot over germany like:
"xxx, descent level 300, 2000 feet per minute or greater"
and when recieving lower level, while still in the descent, they often say something like:
"xxx, descent level 240, given rate"
sometimes they also have us report our given rate to the next sector.
On that subject, i have a question to you controllers:
if descending at 2000fpm, i am going to reduce it to maximum 1500fpm when i get to a 1000' from my cleared level. is it something you expect?
we get these v/s clearances a lot over germany like:
"xxx, descent level 300, 2000 feet per minute or greater"
and when recieving lower level, while still in the descent, they often say something like:
"xxx, descent level 240, given rate"
sometimes they also have us report our given rate to the next sector.
On that subject, i have a question to you controllers:
if descending at 2000fpm, i am going to reduce it to maximum 1500fpm when i get to a 1000' from my cleared level. is it something you expect?
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747dieseldude, yes we would expect you to slow your rate of descent down as you approach your cleared level.
BOAC and pprune radar, I totally agree that if an ATCO changes the clearance that he had previously given, then the new clearance supercedes the old one & all previous restrictions are cancelled unless reiterated by the ATCO.
I am saying that because the aircraft is being transferred between sectors, the receiving ATCO believes the pilot is complying with the standing agreement issued by the previous ATCO and then he gives his own clearance of FL??? In real life the restriction given by the previous ATCO is never mentioned as it is expected that the pilot is complying with it.
Any other ATCOs want to help me out????
BOAC and pprune radar, I totally agree that if an ATCO changes the clearance that he had previously given, then the new clearance supercedes the old one & all previous restrictions are cancelled unless reiterated by the ATCO.
I am saying that because the aircraft is being transferred between sectors, the receiving ATCO believes the pilot is complying with the standing agreement issued by the previous ATCO and then he gives his own clearance of FL??? In real life the restriction given by the previous ATCO is never mentioned as it is expected that the pilot is complying with it.
Any other ATCOs want to help me out????
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DTY/LKS,
Would like to help you out on this one but it doesn't matter who gave the original clearance. It is inherent on the initiator of the clearance to ensure the pilot will do as instructed. Just because the aircraft is transferred and given a subsequent clearance doesn't neccessarily mean the 1st restriction will be applied, although we would all hope that it would be.
Maybe it is time to put pressure on to get the AIP amended.
Would like to help you out on this one but it doesn't matter who gave the original clearance. It is inherent on the initiator of the clearance to ensure the pilot will do as instructed. Just because the aircraft is transferred and given a subsequent clearance doesn't neccessarily mean the 1st restriction will be applied, although we would all hope that it would be.
Maybe it is time to put pressure on to get the AIP amended.
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Originally Posted by 250 kts
Maybe it is time to put pressure on to get the AIP amended.
7 Amendments to Clearances
7.1 When an amendment is made to a clearance the new clearance shall be read in full to the pilot and shall automatically cancel any previous clearance. Controllers must be aware, therefore, that if the original clearance included a restriction, e.g. 'cross ABC FL 150 or below' then the issue of a revised clearance automatically cancels the earlier restriction, unless it is reiterated with the revised clearance.
7.2 Similar care must be exercised when a controller issues a clearance, which amends the route or vertical profile of an aircraft on a standard instrument departure (SID). For example, 'Climb FL 120' automatically cancels the vertical profile of the SID. If the profile contains a restriction which provides vertical separation from conflicting traffic on another SID route, the restriction must be reiterated, e.g. 'climb FL120 cross XYZ 5000 feet or above', unless separation is ensured by other means.
7.3 Similarly, when controllers issue instructions, which amend the SID route, they are to confirm the level profile to be followed e.g. 'fly heading 095 degrees, climb FL 80' or 'route direct to EFG, stop climb at altitude 5000 feet'.
7.1 When an amendment is made to a clearance the new clearance shall be read in full to the pilot and shall automatically cancel any previous clearance. Controllers must be aware, therefore, that if the original clearance included a restriction, e.g. 'cross ABC FL 150 or below' then the issue of a revised clearance automatically cancels the earlier restriction, unless it is reiterated with the revised clearance.
7.2 Similar care must be exercised when a controller issues a clearance, which amends the route or vertical profile of an aircraft on a standard instrument departure (SID). For example, 'Climb FL 120' automatically cancels the vertical profile of the SID. If the profile contains a restriction which provides vertical separation from conflicting traffic on another SID route, the restriction must be reiterated, e.g. 'climb FL120 cross XYZ 5000 feet or above', unless separation is ensured by other means.
7.3 Similarly, when controllers issue instructions, which amend the SID route, they are to confirm the level profile to be followed e.g. 'fly heading 095 degrees, climb FL 80' or 'route direct to EFG, stop climb at altitude 5000 feet'.
Originally Posted by DTY/LKS
I am saying that because the aircraft is being transferred between sectors, the receiving ATCO believes the pilot is complying with the standing agreement issued by the previous ATCO and then he gives his own clearance of FL??? In real life the restriction given by the previous ATCO is never mentioned as it is expected that the pilot is complying with it.
Surely the answer is that, on handover, the pilot will clearly be expected to continue to comply with the clearance given by the previous Sector; however, in the event of further amendments to his clearance by the second Sector, Paragraph 7 (above) MUST apply.
JD
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Standing Agreements
DTY/LKS, I have been re-reading this thread and your earlier posts and there is one further point I would like to put to you.
Don't forget that Standing Agreements are in MATS Part 2, which is confidential to you ATCOs and therefore neither addresed to, nor generally available to, us pilots.
The example you cite, transition from Shannon to MACC at LIFFY, requires descent to make FL270 by LIFFY - as you say to get under LACC Sector 7 above, which I understand has its base at FL285. I totally agree that failure of inbound traffic to make the previously cleared level of FL270 by LIFFY has obvious potential for conflict with either traffic in IOM Sector or Sector 7. Where I disagree with you is with your implication that the pilot has responsibility for complying with the Standing Agreement. He is not operationally aware of any level restriction as a Standing Agreement - he will (or should!) simply comply with the levels he is cleared to at each stage in the descent.
So, when you say ...
... I have to say I think you are absolutely incorrect.
If, on handover, the IOM Controller is in any doubt of the inbound's ability to achieve FL270 by LIFFY, he should reiterate the requirement. If he then issues a further clearance to, say, FL190 and does not restate the LIFFY constraint, then the restriction of FL270 at LIFFY can, quite rightly, be considered to be cancelled and I would suggest that Paragraph 7 (quoted above) clearly indicates this.
The point I am trying to emphasise is that it must be the IOM Sector Controller's responsibilty to ensure that the Standing Agreement is adhered to and not the Pilot's - Pilots are not aware of Standing Agreements per se.
JD
Don't forget that Standing Agreements are in MATS Part 2, which is confidential to you ATCOs and therefore neither addresed to, nor generally available to, us pilots.
The example you cite, transition from Shannon to MACC at LIFFY, requires descent to make FL270 by LIFFY - as you say to get under LACC Sector 7 above, which I understand has its base at FL285. I totally agree that failure of inbound traffic to make the previously cleared level of FL270 by LIFFY has obvious potential for conflict with either traffic in IOM Sector or Sector 7. Where I disagree with you is with your implication that the pilot has responsibility for complying with the Standing Agreement. He is not operationally aware of any level restriction as a Standing Agreement - he will (or should!) simply comply with the levels he is cleared to at each stage in the descent.
So, when you say ...
The IOM ATCO descends you to FL190, therefore the restriction that the previous ATCO gave you still applies as it is not that ATCO that has given you a new clearance. SO the clearance of FL270 at LIFFY still applies.
If, on handover, the IOM Controller is in any doubt of the inbound's ability to achieve FL270 by LIFFY, he should reiterate the requirement. If he then issues a further clearance to, say, FL190 and does not restate the LIFFY constraint, then the restriction of FL270 at LIFFY can, quite rightly, be considered to be cancelled and I would suggest that Paragraph 7 (quoted above) clearly indicates this.
The point I am trying to emphasise is that it must be the IOM Sector Controller's responsibilty to ensure that the Standing Agreement is adhered to and not the Pilot's - Pilots are not aware of Standing Agreements per se.
JD
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Ooooo, I love this one Chaps 
I sit on an airspace user group, do Fam Flights with MAN ATC folk and my Bro is a retired ATC Flight Checker.
What really pisses me off is the fact that in our carbon footprint, tree hugger, save a bit of gas world, we are being forced down early and at more and more restrictive levels - 270 at LIFFY is 4500 feet low on profile into MAN.
Now, if the great and the good of NATS and Shannon determine that this helps offset any holding at a low level, then fair do's - I don't have a problem.
I just wish that please, somewhere, the front end and the steerer's are actually discussing what each department want and can reasonably achieve to help us save fuel. 270 at LIFFY costs us, on an A330, about 500kgs of fuel on each and every descent, say 3 of our aeroplanes each day, 365 days a year, that is 547.5 Tonnes of fuel per year............... I'm sorry, when you multiply that up, it is an aweful waste of fuel just because the ATC guys say we have to comply.
You ATC guys and gals do a wonderful job, don't get me wrong, I just hate the inefficiency of 'the system' that drives it and don't know how or who to contact
I sit on an airspace user group, do Fam Flights with MAN ATC folk and my Bro is a retired ATC Flight Checker.
What really pisses me off is the fact that in our carbon footprint, tree hugger, save a bit of gas world, we are being forced down early and at more and more restrictive levels - 270 at LIFFY is 4500 feet low on profile into MAN.
Now, if the great and the good of NATS and Shannon determine that this helps offset any holding at a low level, then fair do's - I don't have a problem.
I just wish that please, somewhere, the front end and the steerer's are actually discussing what each department want and can reasonably achieve to help us save fuel. 270 at LIFFY costs us, on an A330, about 500kgs of fuel on each and every descent, say 3 of our aeroplanes each day, 365 days a year, that is 547.5 Tonnes of fuel per year............... I'm sorry, when you multiply that up, it is an aweful waste of fuel just because the ATC guys say we have to comply.
You ATC guys and gals do a wonderful job, don't get me wrong, I just hate the inefficiency of 'the system' that drives it and don't know how or who to contact
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DTY/LKS,
The restriction must be restated if you still require it. A new clearance cancels the restriction.
..
Agreed, however any ATC intervention is going to cost fuel. Any level restriction, vector, speed control, holding, waiting for takeoff.... What is the safe alternative. I suggest that the other alternative is late descent and more track miles.
The restriction must be restated if you still require it. A new clearance cancels the restriction.
..
What really pisses me off is the fact that in our carbon footprint, tree hugger, save a bit of gas world, we are being forced down early and at more and more restrictive levels - 270 at LIFFY is 4500 feet low on profile into MAN.
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Don't forget that Standing Agreements are in MATS Part 2, which is confidential to you ATCOs and therefore neither addresed to, nor generally available to, us pilots.
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The LAM 3A does not have 'published levels', but advisory levels to be confirmed by ATC. There seems to be poor understanding of ATC clearances concerning descent restrictions. Perhaps CAA SRG should step in and make all clearances unambiguous in the R/T phraseology used?