ATC antagonism on descent into LHR
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Thanks to JD for the info a few post's back about cost indexes. Very interesting. 
I suppose I've always had to save time on the a/c as a priority. Saving fuel is good for us but not if it makes the flight longer. This is due to low utilization of the a/c.
I think, as you radar guys have learned to expect certain speeds from each type as they enter your sector, it might be normal to expect the 777 to be doing 320kt or so and then you can plan accordingly. If it is much slower, I expect you have to make a new plan....
The other extreme would be the slower speed of a 146 or Citation II that I few once with a Vmo of 262kt (it's funny how the Vmo horn CB never gathered any dust
) We realised that we were an aerial roadblock and tried to fit as best we could. i.e. at LL, we did 160 to 2d to offset the slow Vref of around 100kt, and then tried for the 1st exit. I've done 180 to 2d in a 125 as a kind request from Geneva - no problem. Being flexible is all part of the job and is also good fun. We couldn't go fast but we could go down and slow down well.
I think the 250kt descent mentioned is fine going into say Antigua, Tobago (only jealous
) or anywhere that's quiet so long it doesn't inconvenience anyone else. The SOP's could perhaps take that into account when sneaking up on London. If I had descended the Citation at a speed close to best glide it would have been less than 200kt!
If it is within the flight envelope of the a/c and there are no real fuel or tech issues then I believe we should all try to fit in with the traffic.
I suppose I've always had to save time on the a/c as a priority. Saving fuel is good for us but not if it makes the flight longer. This is due to low utilization of the a/c.
I think, as you radar guys have learned to expect certain speeds from each type as they enter your sector, it might be normal to expect the 777 to be doing 320kt or so and then you can plan accordingly. If it is much slower, I expect you have to make a new plan....
The other extreme would be the slower speed of a 146 or Citation II that I few once with a Vmo of 262kt (it's funny how the Vmo horn CB never gathered any dust
) We realised that we were an aerial roadblock and tried to fit as best we could. i.e. at LL, we did 160 to 2d to offset the slow Vref of around 100kt, and then tried for the 1st exit. I've done 180 to 2d in a 125 as a kind request from Geneva - no problem. Being flexible is all part of the job and is also good fun. We couldn't go fast but we could go down and slow down well.I think the 250kt descent mentioned is fine going into say Antigua, Tobago (only jealous
) or anywhere that's quiet so long it doesn't inconvenience anyone else. The SOP's could perhaps take that into account when sneaking up on London. If I had descended the Citation at a speed close to best glide it would have been less than 200kt! If it is within the flight envelope of the a/c and there are no real fuel or tech issues then I believe we should all try to fit in with the traffic.
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I'm glad we're not getting into a willy waving contest that unfortunately prevails in a lot of threads these days.
.....
As for the master servant thing. Lets just say that I don't see it that way either. I mean, they love themselves enough already without ATC kissing their butts
.....
As for the master servant thing. Lets just say that I don't see it that way either. I mean, they love themselves enough already without ATC kissing their butts
... or is ferris's abrasive attitude rubbing off on you too ... ?
JD
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Jumbo,
The last sentence you quote is made with tongue planted in firmly cheek and filed under (attempted) humour! As for being abrasive? Who me, a Scot - never
Out of interest Jumbo, when submitting their post-flight/route report (as I assume they all do) is there any section that allows crews to mention any ATC issues encountered? Seems to me that if there is/were such a section, it would remind flight crews to contact ATC if there are issues that they wish to discuss and, perhaps, negate the use of PPRUNE to indirectly raise complaints. Clearly there would be issues with foreign ATS providers and indeed foreign crews. But it would allow UK-based crews to perhaps put these things 'to bed' with our (UK) ATS units before they grow any horns. Just a thought......
Regards,
Jock
The last sentence you quote is made with tongue planted in firmly cheek and filed under (attempted) humour! As for being abrasive?
Who me, a Scot - neverOut of interest Jumbo, when submitting their post-flight/route report (as I assume they all do) is there any section that allows crews to mention any ATC issues encountered? Seems to me that if there is/were such a section, it would remind flight crews to contact ATC if there are issues that they wish to discuss and, perhaps, negate the use of PPRUNE to indirectly raise complaints. Clearly there would be issues with foreign ATS providers and indeed foreign crews. But it would allow UK-based crews to perhaps put these things 'to bed' with our (UK) ATS units before they grow any horns. Just a thought......
Regards,
Jock
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Really sorry, WJMcP - the irony went straight past me ... 
... taking myself too seriously again ... 
Yes, certainly any ATC issues can be raised post-flight in a report and, if appropriate, an MOR can be raised - by either you or us, of course.
However, generally I would have thought most problems are best dealt with by a phone call direct on arrival - wherever possible - to chat over any details while the issue is current, as indeed I suggested in an earlier post. In practice, this does require the initiative to be taken by the pilot and I always think it is a pity more do not do so; I hope you would agree.
In the broad scheme of things, we are all in the same business - so we should keep in touch ...
JD
... taking myself too seriously again ... Yes, certainly any ATC issues can be raised post-flight in a report and, if appropriate, an MOR can be raised - by either you or us, of course.
However, generally I would have thought most problems are best dealt with by a phone call direct on arrival - wherever possible - to chat over any details while the issue is current, as indeed I suggested in an earlier post. In practice, this does require the initiative to be taken by the pilot and I always think it is a pity more do not do so; I hope you would agree.
In the broad scheme of things, we are all in the same business - so we should keep in touch ...
JD
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This has been done before when the fuel price went up to $130/barrel, all of a sudden airliners were all operating at slower more efficient speeds.
Its frustrating listening to "I was doing it cos it was SOP", as economically/not safety derived SOPS should not really feature into a controllers planning for somewhere as busy as London.
Stand timing is a load of boll0ks, as an additional bit of vectoring to get you behind faster traffic should not mean you miss your stand after a 6-9 hour flight. Besides what if the delayed traffic behind had departed late and was struggling not to miss slots/stands and trying to make up time, the OP checked with ground to make sure the traffic behind was on time which made me chuckle becasue if ground had remarked that "no he's missed his stand and parked up on a taxiway" it would have been way to late anyway!
Im surprised the OP didn't offer the increase in speed not only to help streaming but his colleague behind , otherwise you have the the strange situation where fuel policy for another operator is being dictated to by the non safety derived SOPs of others.
Until all airlines are operating the same aircraft or High level SLP's are put in place common sense must prevail for all involved, I must say another 20-30 knots in this instance would have represented a good compromise and as far as CI SOP is concerned, deviating from it for 10-15 mins at the end of a long haul flight in the descent would not have enlarged the hole in the ozone layer or broke the bank at BA. as ultimately its the p1's decision on how to fly the aircraft within the remit of the AOM, or is it?
Its frustrating listening to "I was doing it cos it was SOP", as economically/not safety derived SOPS should not really feature into a controllers planning for somewhere as busy as London.
Stand timing is a load of boll0ks, as an additional bit of vectoring to get you behind faster traffic should not mean you miss your stand after a 6-9 hour flight. Besides what if the delayed traffic behind had departed late and was struggling not to miss slots/stands and trying to make up time, the OP checked with ground to make sure the traffic behind was on time which made me chuckle becasue if ground had remarked that "no he's missed his stand and parked up on a taxiway" it would have been way to late anyway!
Im surprised the OP didn't offer the increase in speed not only to help streaming but his colleague behind , otherwise you have the the strange situation where fuel policy for another operator is being dictated to by the non safety derived SOPs of others.
Until all airlines are operating the same aircraft or High level SLP's are put in place common sense must prevail for all involved, I must say another 20-30 knots in this instance would have represented a good compromise and as far as CI SOP is concerned, deviating from it for 10-15 mins at the end of a long haul flight in the descent would not have enlarged the hole in the ozone layer or broke the bank at BA. as ultimately its the p1's decision on how to fly the aircraft within the remit of the AOM, or is it?
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This thread would not even have been started if anyone other than company traffic was being delayed. With the advent of TCAS as soon as you start slowing someone when they don`t expect it or choosing a tactical heading to create a few extra track miles pilots want to know why.
Contrary to Anotherthing`s opinion I can`t see that the ATCO did anything wrong. By all means NW1 fly to your company/aicraft sops but sit down and think about what you would do if you had more than one aircraft to look after.
So I guess I`m with Ferris on this, neither ATCO`s nor Pilots see the complete picture but controllers see a whole lot more of it.
Contrary to Anotherthing`s opinion I can`t see that the ATCO did anything wrong. By all means NW1 fly to your company/aicraft sops but sit down and think about what you would do if you had more than one aircraft to look after.
So I guess I`m with Ferris on this, neither ATCO`s nor Pilots see the complete picture but controllers see a whole lot more of it.
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Jumbo,
No problems. I agree entirely with your sentiments about pilots touching base if there is anything 'relatively minor' (outwith MOR territory) to discuss/clarify. I was just wondering whether there was any mileage in having a reminder, post flight, to phone ATC if there was anything you wished to query - it might help in promote a better two-way flow and prevent potential 'internet' sniping.
Just out of interest, do the guys down south (TC etc) ever get involved in airline/ATC forums. Round my neck of the woods they have not happened for a while and I think there is a lot to gained from these as well. A few presentations, group discussion and then retire to the bar for a more informal discussion - it always seemed go down well on allsides. Do the guys down south do that and do they get the same sort of benefit from them. I know times are busy and hard, but I think they help.
Jock
No problems. I agree entirely with your sentiments about pilots touching base if there is anything 'relatively minor' (outwith MOR territory) to discuss/clarify. I was just wondering whether there was any mileage in having a reminder, post flight, to phone ATC if there was anything you wished to query - it might help in promote a better two-way flow and prevent potential 'internet' sniping.
Just out of interest, do the guys down south (TC etc) ever get involved in airline/ATC forums. Round my neck of the woods they have not happened for a while and I think there is a lot to gained from these as well. A few presentations, group discussion and then retire to the bar for a more informal discussion - it always seemed go down well on allsides. Do the guys down south do that and do they get the same sort of benefit from them. I know times are busy and hard, but I think they help.
Jock
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WJMcP, there is no formal reminder as such as far as I am aware - but I have always tried to encourage others to do so, whenever the situation has arisen, as a topical chat is so much better than a written report/request, received weeks after the event. In the distant past I have called upon TC, when they were at West Drayton, as it was relatively near to my base (LL), and also once or twice to the (old) LLTWR - but not recently.
JD
JD
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The controller should have sped up the first one, unless it was a simple sequence of two.
"For sequencing/separation, increase to 300k"
IMHO there should be a rule that above ten jets descend at 295 +/- 15kts unless advise (before descent point) or instructed otherwise.
The cost index is BS as referred to earlier it only provides system-wide savings if you're the only aircraft in the sky, anyhoo it's all moot with low oil prices.
"For sequencing/separation, increase to 300k"
IMHO there should be a rule that above ten jets descend at 295 +/- 15kts unless advise (before descent point) or instructed otherwise.
The cost index is BS as referred to earlier it only provides system-wide savings if you're the only aircraft in the sky, anyhoo it's all moot with low oil prices.
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From a different angle, my personal feelings are that it is generally better to reduce an aircraft's speed in the descent for spacing than to accelerate it. For example, if you speed up the first aircraft, he will have two options. Either he will lower the nose, increase forward speed and rate of descent and therefore arrive at the lower level earlier - then he spends more time at the lower level with increased power burning more fuel and making more noise in level flight approaching the holding fix; or, he will simply add power and maintain the same descent profile, in which case he will need speed brake to decelerate at the end of the descent prior to the fix, which is neither fuel-efficient nor a comfortable experience for the fare-paying passengers. I know nothing is simple but I happen to believe you have gone for the wrong option in this case.
In any event and however you look at it, the increasing speed option is almost certainly overall the less energy-efficient one.
I would have thought that the parallel headings option, if feasible, would the best all-round solution - but decisions in that area are clearly more your responsibility than mine ...
JD
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JD, I disagree. You are still thinking about one aircraft. If you leave the first a/c going slow, you HAVE TO SLOW THE NEXT (and all subsequent) a/c, which puts the next a/c in an inefficient state. Your (very good) description of what happens when ATC fiddle with a descent (by applying speeds) also assumes that the descent has already commenced. A/c armed with the knowledge of what speed will be required on descent can adjust TOD, profile etc accordingly to achieve a better outcome. Conversely, if ATC had KNOWN in advance that this 777 was going to descend at 250kts, Im sure there could've been better planning, and a different result.
None of this addresses runway utilisation (as someone alluded to earlier), and the effect of under-utilizing the tarmac that slowing everyone down behind the 777 might've had (burning the slot you would've expected the 777 to fill).
When oil gets back to $150/b maybe someone will make a lot of money designing equipment /software that takes all the factors involved into account (already have/has?)?
None of this addresses runway utilisation (as someone alluded to earlier), and the effect of under-utilizing the tarmac that slowing everyone down behind the 777 might've had (burning the slot you would've expected the 777 to fill).
When oil gets back to $150/b maybe someone will make a lot of money designing equipment /software that takes all the factors involved into account (already have/has?)?
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ferris, nice to have you back in a sensible discussion ...
You make a good point that options are different once the descent for each aircraft has started. My reply was on the basis that both were already established in the descent, as I understood that to be the position in the original thread question. I fully accept that a better solution would have been to anticipate the potential descent conflict by agreeing the descent speeds with the aircraft, well before either have reached TOD. Don't forget, incidentally, that the TOD position will itself vary, depending on the descent speed chosen.
Your suggestion that
is a valid point. However the end result of the alternative is that all aircraft in the sequence are then forced to maintain the higher speed descent, which may well not be their individual preference - indeed some may even decline if they are tight on fuel. Furthermore, if you are holding at the fix anyway, perhaps the "horizontal holding" effect of the slower speed would be preferable for that reason and help the TC controller.
I understand you reasoning but I still feel that, if you have to impose a speed against the aircraft's original preference, it should be the slower speed rather than the faster one.
JD
You make a good point that options are different once the descent for each aircraft has started. My reply was on the basis that both were already established in the descent, as I understood that to be the position in the original thread question. I fully accept that a better solution would have been to anticipate the potential descent conflict by agreeing the descent speeds with the aircraft, well before either have reached TOD. Don't forget, incidentally, that the TOD position will itself vary, depending on the descent speed chosen.
Your suggestion that
If you leave the first a/c going slow, you HAVE TO SLOW THE NEXT (and all subsequent) a/c, which puts the next a/c in an inefficient state.
I understand you reasoning but I still feel that, if you have to impose a speed against the aircraft's original preference, it should be the slower speed rather than the faster one.
JD
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JD, the discussion has become sensible because the thread has morphed away from the topic. The topic is ridiculous, and, IMHO, the guy who started it is totally deserving of an "appropriate" response. It is interesting that some of those who were 'outraged' have deleted their posts....
Anyway...
A lot of stuff is fine in theory, but in the part of the world where I currently work, we employ very unsophiscated techniques which include pushing a/c down early in order to get them to low levels where speed control and vectoring have more effect. The constraints are totally different. Efficiency is not part of the equation (yet). CDAs are a good start (and there is plenty of info available about how much fuel is being saved), but until a total, system-wide, linked communication, slots/flow/optimum level and descent type scenario emerges (and it will), we (individual ATCs) are just playing a minor role using tactical decision making. Computer systems and comms are complex enough to achieve it now, but until there is a driver (like expensive oil/carbon emission penalties etc.) we just do it the way we do.
Anyway...
A lot of stuff is fine in theory, but in the part of the world where I currently work, we employ very unsophiscated techniques which include pushing a/c down early in order to get them to low levels where speed control and vectoring have more effect. The constraints are totally different. Efficiency is not part of the equation (yet). CDAs are a good start (and there is plenty of info available about how much fuel is being saved), but until a total, system-wide, linked communication, slots/flow/optimum level and descent type scenario emerges (and it will), we (individual ATCs) are just playing a minor role using tactical decision making. Computer systems and comms are complex enough to achieve it now, but until there is a driver (like expensive oil/carbon emission penalties etc.) we just do it the way we do.
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The problem with making both fly at the slower speeds is that while the first will make the standing agreement to the next sector, the one that is slowed down won't. You can't go down and slow down as we are always told. If both aircraft have been told which level to expect to meet by which point and then start down when they reach TOD for that level and then fly the different speeds then the one in front will have to speed up so that the next one makes the level out. If you tell us early that your speed in the descent is going to be slower than normal then we can accomodate that.
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A typical fuel-saving descent for a 74 might be around 270kts - is this what you would describe as "normal"? A lighter aircraft obviously would be that much slower. If the clearance is FL250 by Logan (with no speed constraint) that is one thing - FL110 (say) by LAM with the associated SLP and possible further speed reduction for hold entry to comply with, is quite another.
Yes, you are quite right, it is difficult to go down and slow down. Any reduction in speed in the descent will either result in a reduced rate of descent while the speed reduces, or require the use of speed brake, which is not generally regarded as "passenger-friendly".
The crux of the matter is that, once the TOD (planned on a particular descent speed) is passed, it is much easier (but fuel inefficient) to speed up, rather than slow down at that stage. However, the conundrum is that, if you have embarked on a fuel efficient (i.e. relatively slow) descent, it is probably because you are concerned about the fuel burn to some degree, whether it is just economy of operation or fuel actually available in tanks at that time. It is therefore irritating to be asked to speed up halfway through the descent, and therefore use more fuel in the process. The following aircraft, however, if asked to slow down, should not use more fuel but will still have to adjust in some way for this in order to maintain his planned/cleared descent profile.
I am thinking that all of this really points to the need to establish the descent speed for both aircraft before TOD - or, alternatively, to be flexible enough to be able to vector in the descent for a possible parallel handover because of the different groundspeeds. I do understand that this becomes increasing more difficult the nearer to the end of descent (and therefore nearer to the holding fix) that each aircraft is, also that the approach sequence may be affected as a result.
JD
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Glad to see that things are the same the world over. When we were sendin' and blendin' them -- over here in the colonies -- and some guy in the middle of the pack wanted to do 250 kts we just let him fly at 250. Away from the aiport.
I realize that all controllers are psychotic but can you really blame us ? One day you want to go fast to make your connections. One day you want to go slow to save fuel. One day you want to be high to save gas. The next day you want to be low because of the turbulence, etc., etc., etc.
Somebody had it right. Just shoot the guy that writes the SOPs so we only have to guess what the Captain wants to do...on this flight.
And....whoever else said...
It's the runways, Stupid.
Time is money. We're here to serve. Etc., etc., etc.
Don Brown
I realize that all controllers are psychotic but can you really blame us ? One day you want to go fast to make your connections. One day you want to go slow to save fuel. One day you want to be high to save gas. The next day you want to be low because of the turbulence, etc., etc., etc.
Somebody had it right. Just shoot the guy that writes the SOPs so we only have to guess what the Captain wants to do...on this flight.
And....whoever else said...
It's the runways, Stupid.
Time is money. We're here to serve. Etc., etc., etc.
Don Brown
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I was doing 10km/h down the highway yesterday (as per my conservative SOPs), and a police officer said that I was slowing the traffic down...antagonistic pr!ck (he obviously has no common sense!)
New thread to come???
I must take the same tablets as Don Brown, (and Ferris)!
BTW, the school 'drop off' today, where 100 children start at 8.40am (I'm thinking airline schedules now), caused me to slow down, speed up, stop, and GO, all in the one trip!
I will be submitting an official complaint, and demanding a 60 km/h steady drive to the school tomorrow, direct to a parking spot, and have all other cars stop while I walk my children to their classroom. Regardless of all other road users (I will save on fuel, time, engine wear, etc).
Big picture...no.
Big problems...Ditto!
MAN UP and face reality.
This forum a joke...I think it is.
TB.
P.S Don't say anything that upsets me...or I will start a '2nd' thread!
New thread to come???
I must take the same tablets as Don Brown, (and Ferris)!
BTW, the school 'drop off' today, where 100 children start at 8.40am (I'm thinking airline schedules now), caused me to slow down, speed up, stop, and GO, all in the one trip!
I will be submitting an official complaint, and demanding a 60 km/h steady drive to the school tomorrow, direct to a parking spot, and have all other cars stop while I walk my children to their classroom. Regardless of all other road users (I will save on fuel, time, engine wear, etc).
Big picture...no.
Big problems...Ditto!
MAN UP and face reality.
This forum a joke...I think it is.
TB.
P.S Don't say anything that upsets me...or I will start a '2nd' thread!
