LHR mixed mode trial
Nevertheless. If Gatwick single runway ops can deliver over 50 per hour on one runway that kinda points at 100/hr at LHR. Or am I missing something?
I've read estimates that LHR could accommodate around up to 15% more movements without extending the operating day if full mixed mode was used on both runways. That would be a more realistic comparison with LGW's capacity.
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DaveReid,
Both. Yes, confusing, isn't it?
There is no restriction to landing on 09R. However, in general we can only depart on 09R due to Cranford. Therefore, in general, the level of outbound demand precludes using 09R for arrivals a lot of the time. It's down to the individual controllers to offer spare capacity to the inbounds.
However, when the delay builds up on easterlies, we tend to use the same level of delay to provide the same rate of arrivals (6 per hour) as on westerlies, hence it can still bew referred to as TEAM.
SGC, under current understanding of SOIR9643, LHR is not equipped for independent approaches or departures.
Both. Yes, confusing, isn't it?
There is no restriction to landing on 09R. However, in general we can only depart on 09R due to Cranford. Therefore, in general, the level of outbound demand precludes using 09R for arrivals a lot of the time. It's down to the individual controllers to offer spare capacity to the inbounds.
However, when the delay builds up on easterlies, we tend to use the same level of delay to provide the same rate of arrivals (6 per hour) as on westerlies, hence it can still bew referred to as TEAM.
SGC, under current understanding of SOIR9643, LHR is not equipped for independent approaches or departures.
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LCYslicker :
In addition to the daily and monthly reports provided by BAA, the CAA have published an early interim report to the Aviation Minister with information on the trial as carried out in November and December.
It gives some more independent analysis of how many additional TEAM* flights have taken place .
http://www.caa.co.uk/default.aspx?ca...0&pageid=13041
In addition to the daily and monthly reports provided by BAA, the CAA have published an early interim report to the Aviation Minister with information on the trial as carried out in November and December.
It gives some more independent analysis of how many additional TEAM* flights have taken place .
http://www.caa.co.uk/default.aspx?ca...0&pageid=13041
There is no restriction to landing on 09R. However, in general we can only depart on 09R due to Cranford. Therefore, in general, the level of outbound demand precludes using 09R for arrivals a lot of the time. It's down to the individual controllers to offer spare capacity to the inbounds.
However, when the delay builds up on easterlies, we tend to use the same level of delay to provide the same rate of arrivals (6 per hour) as on westerlies, hence it can still be referred to as TEAM.
However, when the delay builds up on easterlies, we tend to use the same level of delay to provide the same rate of arrivals (6 per hour) as on westerlies, hence it can still be referred to as TEAM.
I understand the distinction you're making between a planned stream of post-0700 09R landings (to reduce delay) and opportunistic use of 09R for other reasons (e.g. a T4 arrival).
So it would be helpful if the trial stats observed that distinction too. Instead, some days' totals appear to count all 09R landings, including any ad-hoc, isolated non-TEAM movements, but the stats for other easterly days seem to exclude those and only count TEAM.
there is a great deal of misinformation about Operational Freedoms and what is happening at LHR
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The fog extends to the CAA at times :
However, on a number of occasions, there has been some discrepancy between BAA‟s published figures and the CAA‟s interpretation of the data. In most cases, it has been possible to explain the differences, following extra work from NATS and BAA, but this reconciliation is not always apparent from the data which BAA is routinely publishing. (Section 7.9)
and suggest that the Cambridge boffins look closely :A key step in the data validation process for the final report will be ensuring that the two principal sources of data used in measuring use of the trial freedoms (i.e. the Noise and Track-Keeping System and NATS operations logs) are reconciled accurately and consistently so as to provide a robust and reliable picture of the flights that have benefited from the application of the operational freedoms. We would recommend that Cambridge University look specifically at this aspect of data generation as part of their validation role.
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<<Heathrow was built before these rules were developed and the two runways are so far apart that under SOIR they can be counted as independent in all modes of operation.>>
Wish I'd known that during the 31 years I was a Heathrow radar controller. We always provided radar separation twixt the two runways in IMC... or have the rules recently changed?
Wish I'd known that during the 31 years I was a Heathrow radar controller. We always provided radar separation twixt the two runways in IMC... or have the rules recently changed?
The fog extends to the CAA at times :
However, on a number of occasions, there has been some discrepancy between BAA‟s published figures and the CAA‟s interpretation of the data. In most cases, it has been possible to explain the differences, following extra work from NATS and BAA, but this reconciliation is not always apparent from the data which BAA is routinely publishing. (Section 7.9)
and suggest that the Cambridge boffins look closely :A key step in the data validation process for the final report will be ensuring that the two principal sources of data used in measuring use of the trial freedoms (i.e. the Noise and Track-Keeping System and NATS operations logs) are reconciled accurately and consistently so as to provide a robust and reliable picture of the flights that have benefited from the application of the operational freedoms. We would recommend that Cambridge University look specifically at this aspect of data generation as part of their validation role.
Quite so.
Given that the whole point of the trials is to test the effect of variations in runway usage, you would think that counting the number of movements accurately and identifying correctly which runway each one used would be a good idea.
It's hard to see where "interpretation of the data" comes into that.
Given that the whole point of the trials is to test the effect of variations in runway usage, you would think that counting the number of movements accurately and identifying correctly which runway each one used would be a good idea.
It's hard to see where "interpretation of the data" comes into that.
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I guess that interpretation is a bit harder than that - and I don't know how impenetrable the ATC operational logs are to decipher and match up with the NTK data.
There is also the strange category of " Number of aircraft arrivals operated outside the runway alternation pattern (excluding TEAM arrivals or emergencies)" which would be clearer if there was a bit of commentary explaining what was going on. I guess situations where they shift the whole landing runway from the designated one to the other becuase it is more suitable for cross-winds would be approriate to go in that box.
But there is still fog around.......
There is also the strange category of " Number of aircraft arrivals operated outside the runway alternation pattern (excluding TEAM arrivals or emergencies)" which would be clearer if there was a bit of commentary explaining what was going on. I guess situations where they shift the whole landing runway from the designated one to the other becuase it is more suitable for cross-winds would be approriate to go in that box.
But there is still fog around.......
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If Heathrow was to be operated to its full capabilities i.e. no night curfew and full independent mixed mode, then the capacity could be increased by in excess of 40%.
Won't happen, of course, because the BAA would have to build 2 or 3 more terminals to cope with the extra passengers. Not to mention all the associated tube, Heathrow Express expansion that would be required. Might be a bit of a kerfuffle from the Cranford residents too, I guess. And I'm not even going to mention politicians.
It would be interesting to see if the costs of compulsory purchase of all the noise-affected houses around LHR would be greater than building "Ebbsfleet-in-the-Marsh International Airport". Probably take just as long.
Meanwhile in Amsterdam the other morning, in a three hour period whilst I was waiting for a connecting flight, there were flights to Edinburgh, Glasgow, Newcastle, Manchester, Birmingham, Bristol, East Midlands, Southampton, Aberdeen, Norwich, Cardiff, Luton, Liverpool, Leeds Bradford, Stansted, Durham Tees Valley, London City, London Gatwick and even a couple to Heathrow. Most were KLM Cityhopper B737-800s, even one of the Heathrows, so over 4,000 passengers. Now I know Amsterdam has its attractions but not on a sub-zero February morning. I would imagine more than 50% of those travelling, like me, were connecting because they couldn't get the flights they used to via Heathrow. This was a real surprise for me and just goes to show how much traffic is being lost by Heathrow - over 2,000 "customers" in just 3 hours and from just one European Airport.
On the beach
P.S. Our flight and the Glasgow flight were overbooked, too.
P.P.S. Forget the mixed-mode trial. It works. Just like it does everywhere else in the world. Hurry up and get on with implementing it before LHR becomes just an anachronism.
Won't happen, of course, because the BAA would have to build 2 or 3 more terminals to cope with the extra passengers. Not to mention all the associated tube, Heathrow Express expansion that would be required. Might be a bit of a kerfuffle from the Cranford residents too, I guess. And I'm not even going to mention politicians.
It would be interesting to see if the costs of compulsory purchase of all the noise-affected houses around LHR would be greater than building "Ebbsfleet-in-the-Marsh International Airport". Probably take just as long.
Meanwhile in Amsterdam the other morning, in a three hour period whilst I was waiting for a connecting flight, there were flights to Edinburgh, Glasgow, Newcastle, Manchester, Birmingham, Bristol, East Midlands, Southampton, Aberdeen, Norwich, Cardiff, Luton, Liverpool, Leeds Bradford, Stansted, Durham Tees Valley, London City, London Gatwick and even a couple to Heathrow. Most were KLM Cityhopper B737-800s, even one of the Heathrows, so over 4,000 passengers. Now I know Amsterdam has its attractions but not on a sub-zero February morning. I would imagine more than 50% of those travelling, like me, were connecting because they couldn't get the flights they used to via Heathrow. This was a real surprise for me and just goes to show how much traffic is being lost by Heathrow - over 2,000 "customers" in just 3 hours and from just one European Airport.
On the beach
P.S. Our flight and the Glasgow flight were overbooked, too.
P.P.S. Forget the mixed-mode trial. It works. Just like it does everywhere else in the world. Hurry up and get on with implementing it before LHR becomes just an anachronism.
There is also the strange category of " Number of aircraft arrivals operated outside the runway alternation pattern (excluding TEAM arrivals or emergencies)" which would be clearer if there was a bit of commentary explaining what was going on. I guess situations where they shift the whole landing runway from the designated one to the other because it is more suitable for cross-winds would be appropriate to go in that box.
Having said that, the only day where the stats do show a sizeable "operated outside the runway alternation pattern" total (35, in fact) was a couple of weeks later (Sun 18th December) when the exactly same thing happened - strong SSW winds resulting in 27L being used for a couple of spells in the late afternoon.
Go figure.
And then there are out-of-alternation landings that aren't counted at all, like last Friday evening's BMI from Vienna, which landed between a couple of 27R departures. The "post-0700 TEAM" and "out of alternation" totals for that day are both zero, so was it therefore classed as an emergency landing ?
The sad part is that, now Phase I of the trial is over, some serious debate and decision-making on Future Heathrow needs to happen (cf On the Beach's post) - but that process doesn't stand a chance if the various parties involved can't even agree over basic statistics on what happened during the trial.
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I knew this subject was complicated, but not THIS complicated!
Thanks, chaps, for a most enlightening thread - I'm glad that the right people understand it.
Lucky the current govt has ruled out the 3rd parallel runway, then, otherwise it would get extremely complicated.
For what it's worth, London ATC and 4 airports handle more passengers per annum in aggregate than any other city - NYC comes next (though it handles more movements = more t/props). But note PEK alone has just overtaken LHR.
Thanks, chaps, for a most enlightening thread - I'm glad that the right people understand it.
Lucky the current govt has ruled out the 3rd parallel runway, then, otherwise it would get extremely complicated.
For what it's worth, London ATC and 4 airports handle more passengers per annum in aggregate than any other city - NYC comes next (though it handles more movements = more t/props). But note PEK alone has just overtaken LHR.
I knew this subject was complicated, but not THIS complicated!
Counting movements, and recording which runway they used, and why, is hardly rocket science. I don't believe for a moment that NATS aren't doing that part properly.
Yet the CAA, in their progress report on the trial, talk about "discrepancies in the published figures" and "queries on the consistency of the data", together with a pointed reminder to all concerned that the trial needs to produce data "sufficient to generate a robust information-base on which Government can ultimately take decisions".
I can see the CAA's point, though - for example the stats would have us believe that 100% of last Monday's movements were easterlies, when in fact the whole day was westerlies.
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Counting movements, and recording which runway they used, and why, is hardly rocket science. I don't believe for a moment that NATS aren't doing that part properly.
However, the benefit for each particular flight is very much more difficult to ascertain when looked at in isolation. Did the out of alternation arrival occur because of Ops Freedoms? Or would it have TEAMed anyway in a pre-Ops Freedoms world? If we 'Ops Freedoms' TEAMed 3 an hour over two hours, would we have 'standard' TEAMed 6 in the second hour before? Yes, it's probably better because it implies less airborne holding, but is it looked at as 6 extra arrivals? Did the fact that we used some of the pro-active tests such as landing the A380 and T4 traffic on the departure runway cause a build up in departure delay?
Add all that to the common misconception that standard TEAM of 6 per hour gives you 6 extra arrivals per hour, and it all gets rather complicated!
The why can be missed sometimes, it depends on priorities at the time. Most whys can be worked out afterwards, again if there is time, or purely from the stats.
"Although it appears from these figures that there were a significant number of days during the proactive test period when the TEAM* freedoms were not used proactively, it may be that landing A380s, small aircraft or T4 arrivals out of alternation on these days has been captured under the reactive TEAM* totals. When the reactive trigger conditions are also met, it is not always possible to say under which variant of the freedom an aircraft was landed."
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Another source of confusion is the treatment of which days night flights are assigned to.
The daily reports all have "Date that data relates to (from 00:00 hrs to 23:59 local time)" on the top line of the report.
However the info for Saturday 4th February (one of the snow days) actually covers the period 04:30 Saturday 4th February to 04:30 on Sunday 5th February.
Hence the continual stream of departures that took off over Cranford in the early hours of Sunday are attributed to Saturday's report and not to Sunday !!
Odd that they clarify the timing of the data on the first line and then don't actually report the info on that basis.
The daily reports all have "Date that data relates to (from 00:00 hrs to 23:59 local time)" on the top line of the report.
However the info for Saturday 4th February (one of the snow days) actually covers the period 04:30 Saturday 4th February to 04:30 on Sunday 5th February.
Hence the continual stream of departures that took off over Cranford in the early hours of Sunday are attributed to Saturday's report and not to Sunday !!
Odd that they clarify the timing of the data on the first line and then don't actually report the info on that basis.
Another source of confusion is the treatment of which days night flights are assigned to.
The daily reports all have "Date that data relates to (from 00:00 hrs to 23:59 local time)" on the top line of the report.
However the info for Saturday 4th February (one of the snow days) actually covers the period 04:30 Saturday 4th February to 04:30 on Sunday 5th February.
Hence the continual stream of departures that took off over Cranford in the early hours of Sunday are attributed to Saturday's report and not to Sunday !!
Odd that they clarify the timing of the data on the first line and then don't actually report the info on that basis.
The daily reports all have "Date that data relates to (from 00:00 hrs to 23:59 local time)" on the top line of the report.
However the info for Saturday 4th February (one of the snow days) actually covers the period 04:30 Saturday 4th February to 04:30 on Sunday 5th February.
Hence the continual stream of departures that took off over Cranford in the early hours of Sunday are attributed to Saturday's report and not to Sunday !!
Odd that they clarify the timing of the data on the first line and then don't actually report the info on that basis.
It may also be relevant that the night quota dispensation counts for 4th and 5th February were initially shown as TBC, then values were "added after verification" that were actually higher than the total number of movements (exempt/non-exempt), then they were changed back to TBC with the comment "figures withdrawn pending further analysis".
Given the long-standing statutory requirement to report LHR night quota movements and exemptions to the DfT, you would think that any bugs in the analysis and reporting process would have been ironed out long ago.
The trial period for using LHR's 2 runways in mixed mode is ending soon, with the next period covering the Olympics. My observation is that it has very rarely been used during the trial period. Does anyone in the ATC world want to comment on whether useful experience of mixed mode has been gained?
I guess a good question at this stage would be whether any strategies have emerged from the trial that ATC can continue to use over the intervening period, i.e. measures short of enhanced TEAM/TED but which can be deployed on a day-to-day basis, or will the operating regime in the meantime revert to that which existed pre-trial ?
Incidentally, I understand from the group who are tasked with doing independent validation of the published trial results that they have recommended the stats be withdrawn and re-done to eliminate "incorrect manual data manipulations" which have affected both the daily and monthly figures. I don't know whether that recommendation has been accepted, or if it has, what timescales will be involved for the rework.
I assume this, if done, would address all the various issues mentioned in previous posts: incorrect movement counts, reporting night flights against the wrong day, missing TEAM instances, failing to identify which freedom was applied, wrongly reporting runway usage, etc.