PDA

View Full Version : Vectoring at Gatwick


Simbad
7th Aug 2017, 06:29
Can a controller please remind me why it's not feasible, possible to hold in stacks and then proceed for the procedure rather than being vectored for the approach at Gatwick.

Also re Gatwick, I thought a couple of years ago by an NTC the phraseology was changed to Cleared for the Approach rather than descend on the glide once established on the LOC!

Thanks

Whilst we are at it, what is the definition of "Good Rate" when climbing. Why not specify a rate therefore you know straight away if its possible to achieve said rate.

Thanks Again.

chevvron
7th Aug 2017, 08:47
Traffic inbound to Gatwick is vectored because it is deemed to be 'radar only' approach control , actually done from London Terminal Control at Swanwick. Procedural plates are only for backup in case of an (unlikely) total radar failure.
Radar vectoring is more efficient than procedural approach as separation on final approach can reduce to 2.5nm if there are no departures and slightly more if there are departures whereas it would be time based without radar probably something like 5 minutes, although this would need to be confirmed by someone current on Gatwick Approach.

HEATHROW DIRECTOR
7th Aug 2017, 09:11
Simbad.... as my friend Chevvron says, radar vectoring is more efficient and I'm surprised that as a commercial pilot you do not appreciate this. Every major airfield in Europe employs radar vectoring. If they did not, delays would extend to days, not just minutes! There is no system - yet - which can beat radar control both in terms of safety and expedition.

throw a dyce
7th Aug 2017, 09:13
Simbad,
I think it would be better that you were able to visit an Approach Radar facility anywhere in the world and you'll soon see why you are vectored.Gatwick isn't an exception.
As a controller we were encouraged to see it from the pilots side.Shame more aircrew aren't able to do the same.

Doody2007
7th Aug 2017, 15:43
Although, with the coming of pbn and rnav transitions from the primary holds onto the ILS, I can see a day in the next 5-15 years when radar vectoring onto the ILS will be the exception rather than the norm.

Point merge at Dublin, Copenhagen, Paris and, before long, Manchester, will see the demise of race track holds and radar vectors.

These approaches will remain radar monitored and as such radar separation will be applied rather than procedural, however, they will be pretty much pilot interpreted rather than having controller intervention. The advantage to the pilot, you can see from your fms exactly how far you are from touchdown rather than our best guess allowing you to set up and fly the aircraft as you see fit.

From a controller point of view, a much reduced workload and RT loading allowing us to move more aircraft.

There are drawbacks of course. It only works providing aircraft are reasonably similar in performance, it won't work if the rnav route is taken out due weather or a cat b flight or something like that. It requires a fair bit of airspace to contain point merge arcs.

There may still be a little radar vectoring by a finals director to either tighten up or loosen off a sequence. However, the radar vectoring by an initials controller will go by the way side.

I am a radar controller by the way, and I happen to enjoy the radar vectoring side. Just, I believe it's getting to the point where it's had it's day.

I'm going to go and grab my hard hat now as I'm sure I've just opened the flood gates to all kinds of abuse from fellow professionals. However, before anyone starts, I would ask that you have a look at the various YouTube clips of point merge in action and see that it does work!

Cheers

Not Long Now
7th Aug 2017, 17:06
How does a point merge system with 'arc' provide an exact distance from touchdown? Surely it provides, at best, a 'maximum distance'?
If pilots prefer this to range given by a controller then fair enough, but doesn't exactly seem to be a huge benefit.

Doody2007
7th Aug 2017, 17:42
Routing around the arc is the equivalent to going round the race track hold. You are absolutely correct, the pilots will only have a theoretical maximum distance. However, once cleared to route direct to the merge point, the fms updates the rest of the distance to touchdown.

Pilots are cleared to the merge point as soon as the one ahead is established inbound to the merge point and is the appropriate distance ahead.

It works. When I first heard about it I wasn't convinced either, but I'm slowly coming around to the idea. 😀

Not Long Now
7th Aug 2017, 18:13
I know it works, I'm just not convinced that it has as many benefits as it was 'sold' to have. Like much in air traffic....

HEATHROW DIRECTOR
7th Aug 2017, 18:15
Recall when Concorde started, one of the first officers came up with a brain wave. ATC would simply clear them for a "standard" approach and keep other traffic out of the way. It didn't last because it was a hopeless idea. One day a colleague of mine said to the inbound Conc: "Do you want a standard approach or a hand job?" Conc replied: "A hand job please any time". That's what crews thought of that!

chevvron
7th Aug 2017, 18:47
Routing around the arc is the equivalent to going round the race track hold. You are absolutely correct, the pilots will only have a theoretical maximum distance. However, once cleared to route direct to the merge point, the fms updates the rest of the distance to touchdown.

Pilots are cleared to the merge point as soon as the one ahead is established inbound to the merge point and is the appropriate distance ahead.

It works. When I first heard about it I wasn't convinced either, but I'm slowly coming around to the idea. 😀
All very well for an arrival runway only, but what if you're single runway with lots of departures? And what about the much vaunted 'mixed mode' ops?

Doody2007
7th Aug 2017, 18:58
I'm not going to say anything else about it as I've seen these arguments turn nasty and I have no intention of getting into one.

As a last thought, I asked a local 738 pilot, who regularly flies into Dublin, what he thought of the Point Merge there. I fully expected the answer to be, "we hate it, it takes too long, uses too much fuel, etc". Instead, "we love it, it works a treat for us, we can fly the aircraft according to our range. etc"

As the original poster seems to intimate, the pilots, our customers, seem to want this rather than be radar vectored all over the sky. I know, a fully trained controller can provide accurate ranges to touchdown, but this isn't what the customer seems to want.

With regards to single runway operations, you just let the first aircraft heading to the merge point get a little further ahead before you clear the next aircraft to the merge point, thus building in your gap for a departure that the tower wants. The system can be made to work according to your airport's requirements and ATC needs.

That is all.

Cheers
:O

HEATHROW DIRECTOR
7th Aug 2017, 19:49
"Customer"! Sorry I have never viewed pilots as customers. It's horrible management yuckspeak.

I haven't understood much of this thread (too old probably) but it sounds too much like old fashioned procedural control!

good egg
7th Aug 2017, 21:08
Time based arrival spacing is on the horizon for mixed mode operations. Personally speaking I'd like to see it even earlier than planned.
Aircraft touchdown times are easily predictable, and accurate, with PRNAV approaches and "live" weather.
Artificial Intelligence can also add to the accuracy, using airline/aircraft specific data to predict touchdown time and alert approach controllers if the time-based separation required by the tower controllers is being eroded (or, is being stretched = inefficient).
IMHO it's high time that this technology was employed at mixed mode runways to increase airport efficiency.

(Bug bear of mine.)

Out Of Trim
7th Aug 2017, 21:56
So what happens when ten aircraft, all with the same landing estimate; all converge at once?

DaveReidUK
7th Aug 2017, 22:39
So what happens when ten aircraft, all with the same landing estimate; all converge at once?

I think the idea is that they don't. :O

Nimmer
8th Aug 2017, 04:43
And back to the original question. If aircraft are not regularly vectored out of the holds the TMA have no where to put the incoming planes. We still,regular see the TMA vectoring inbounds all at FL 150 around the Soutn East preying a level will become vacant soon.

As for new techniques, yes they will work, but not without a large scale airspace redesign.LAMP 2 anyone?

System has been creaking badly this year, combine that with low staffing levels and it's going to get ugly!!,

Not Long Now
8th Aug 2017, 08:29
For the last who knows how long, aircraft have been holding for Heathrow 0600 arrival having known the second they turned the keys on the ramp in whichever US airport exactly when they would arrive and theoretically land. Has this resulted in them arriving at an appropriate time for the curfew, let alone the relative to the other 30 inbounds wanting to land first? No. Perhaps the airlines need to agree amongst themselves a landing order, let the aircraft know, and fly appropriately. Then we really all could just sit back and 'monitor' the situation, presuming there's only one airport in the vicinity naturally. I'll be off then of course. The chances of being able to usefully intervene having been just 'monitoring' for the last thousand hours are not appealing.

Reverserbucket
8th Aug 2017, 09:03
"Customer"! Sorry I have never viewed pilots as customersNo HD, and I don't think many ANSP's view the pilot as the customer, however it is the airlines who pay the user charges and who ultimately, will pick up the tab for the incredible amount of money that the EU is currently ploughing into SESAR deployment and the development of future PBN and related implementation through the ANSP's - the idea being that eventually, with future ADS-B 'In' capability, self separation will in fact become a reality and in some ways, perhaps a return to procedural control, but with the FMS maintaining separation and ATC monitoring as suggested by Not Long Now.

I like speaking to a human rather than a computer however and I foresee, rather in the same way we have seen a deterioration in basic handling skills and situational awareness in the airlines through increased technology and automation, a gradual reduction in capacity due to controllers in busy TMA's being unable or unwilling to vector when necessary to help alleviate flow during peak periods. I personally hope that ATC does not go the same way that flight deck philosophy has gone in the last couple of decades where the pilot has been effectively designed out of the system (almost). PBN appears to offer many benefits but ultimately, the path it takes is not being determined by ATM experts or aircrew but largely by lawyers, accountants and the aviation manufacturing industry.

I have had the pleasure of spending much time in the company of civilian controllers from many parts of the world, however now and again (and I mean very occasionally) I have met those who feel, and particularly in the US I discovered, that aircrew are there to make their lives difficult and are largely treated with contempt - where would European ANSP's derive their shareholders profits and pension pots from if not from their customers, the airlines, and their airborne representatives, the pilots?

blissbak
8th Aug 2017, 09:27
what is the definition of "Good Rate" when climbing. Why not specify a rate therefore you know straight away if its possible to achieve said rate.


There is no definition of "good rate", it's not standard, you should be asked to keep the best rate for the best result.

good egg
8th Aug 2017, 16:50
No HD, and I don't think many ANSP's view the pilot as the customer, however it is the airlines who pay the user charges and who ultimately, will pick up the tab for the incredible amount of money that the EU is currently ploughing into SESAR deployment and the development of future PBN and related implementation through the ANSP's - the idea being that eventually, with future ADS-B 'In' capability, self separation will in fact become a reality and in some ways, perhaps a return to procedural control, but with the FMS maintaining separation and ATC monitoring as suggested by Not Long Now.

I like speaking to a human rather than a computer however and I foresee, rather in the same way we have seen a deterioration in basic handling skills and situational awareness in the airlines through increased technology and automation, a gradual reduction in capacity due to controllers in busy TMA's being unable or unwilling to vector when necessary to help alleviate flow during peak periods. I personally hope that ATC does not go the same way that flight deck philosophy has gone in the last couple of decades where the pilot has been effectively designed out of the system (almost). PBN appears to offer many benefits but ultimately, the path it takes is not being determined by ATM experts or aircrew but largely by lawyers, accountants and the aviation manufacturing industry.

I have had the pleasure of spending much time in the company of civilian controllers from many parts of the world, however now and again (and I mean very occasionally) I have met those who feel, and particularly in the US I discovered, that aircrew are there to make their lives difficult and are largely treated with contempt - where would European ANSP's derive their shareholders profits and pension pots from if not from their customers, the airlines, and their airborne representatives, the pilots?

An interesting point. But, realistically speaking, I can see the day (not too far off) when Approach Control is basically a monitoring function - for when sh*t happens.
Every ANSP wants to squeeze costs, which is done by more aircraft with same/less "controllers".
Yes, in bad weather, arrival rates will suffer but in "normal weather" (which, statistically speaking, is the norm) then the reliance will be on technology, with minimal ATCO input.
It's what the world (customer) wants....cheap fares, OTP, etc., etc.
Same goes for Tower controllers....more (accurate) info on arrival touchdown times with warnings provided about when it's safe to clear a departure for take-off etc, until it too is a monitoring function.
Technology creep, first "tools" to assist controllers, then automation/ATC being "monitors".
Not always a bad thing, however - humans make random errors (I'm human, I make them).
We're closer now to the "monitoring function"/"only take over in emergency situation" than we've ever been.
Ye olde controllers will say "yes, but when I started X years ago we were all told that we'd be (effectively) out of a job in 20 years" due to this 'techno creep'. Now, more than ever, this is true. Less ATCOs, less cost. 90% of the time it'll work better/more efficiently/with less cost, and equally safely (if not better).
It's what happens with the other 10% that matters...

Nimmer
8th Aug 2017, 17:57
An interesting point. But, realistically speaking, I can see the day (not too far off) when Approach Control is basically a monitoring function - for when sh*t happens.
Every ANSP wants to squeeze costs, which is done by more aircraft with same/less "controllers".
Yes, in bad weather, arrival rates will suffer but in "normal weather" (which, statistically speaking, is the norm) then the reliance will be on technology, with minimal ATCO input.
It's what the world (customer) wants....cheap fares, OTP, etc., etc.
Same goes for Tower controllers....more (accurate) info on arrival touchdown times with warnings provided about when it's safe to clear a departure for take-off etc, until it too is a monitoring function.
Technology creep, first "tools" to assist controllers, then automation/ATC being "monitors".
Not always a bad thing, however - humans make random errors (I'm human, I make them).
We're closer now to the "monitoring function"/"only take over in emergency situation" than we've ever been.
Ye olde controllers will say "yes, but when I started X years ago we were all told that we'd be (effectively) out of a job in 20 years" due to this 'techno creep'. Now, more than ever, this is true. Less ATCOs, less cost. 90% of the time it'll work better/more efficiently/with less cost, and equally safely (if not better).
It's what happens with the other 10% that matters...

Keep taking those pills good Egg, you will get better soon.

Surferboy
8th Aug 2017, 18:11
And exactly how current will you be to jump in when the **** hits the fan after sitting on your *ss and monitoring for 90% of your working hours?:hmm:

good egg
8th Aug 2017, 18:56
And exactly how current will you be to jump in when the **** hits the fan after sitting on your *ss and monitoring for 90% of your working hours?:hmm:

That's what regulations are for...

Gonzo
8th Aug 2017, 19:03
I've already tested a tool on our electronic strip system that will tell the controller the earliest time of rotation to achieve wake separation based on the rotation time of the leader.

It's part of a SESAR 2020 project.

When we go to pair-wise wake separation for departure, no controller is going to be able to cope without tool support.

good egg
8th Aug 2017, 20:30
I've already tested a tool on our electronic strip system that will tell the controller the earliest time of rotation to achieve wake separation based on the rotation time of the leader.

It's part of a SESAR 2020 project.

When we go to pair-wise wake separation for departure, no controller is going to be able to cope without tool support.

Ah Gonzo, a voice of reason/experience...
...if only there were more like you on here (within recent working memory...)

Gonzo
8th Aug 2017, 21:01
Sadly our job is not to keep our job fun.

If it was I'd still be doing bandboxed ground in the old tower with paper strips, or 09R Deps passing out non-standard CPTs with ten conditionals.

Our job is to safely move the traffic, and try and cone up with ways of doing it better, cheaper, quicker and making that flow of traffic more predictable.

Talkdownman
8th Aug 2017, 21:40
no controller is going to be able to cope without tool support
Hmmm....
If it was I'd still be doing bandboxed ground in the old tower with paper strips, or 09R Deps passing out non-standard CPTs with ten conditionals
Ah, Sweet Neuralgia...

good egg
8th Aug 2017, 21:40
Sadly our job is not to keep our job fun.

If it was I'd still be doing bandboxed ground in the old tower with paper strips, or 09R Deps passing out non-standard CPTs with ten conditionals.

Our job is to safely move the traffic, and try and cone up with ways of doing it better, cheaper, quicker and making that flow of traffic more predictable.

Oh don't sound so dreary about it...I think it's called "challenge"... ;)

Gonzo
9th Aug 2017, 04:07
TDM, if you think you could remember a vortex table which is a 96x96 matrix, with departure separations in 10s increments for each individual type pairing, no more categories, can we use you in the sim?

For example, B772 followed by A321 might be 80s, but followed by an A320 it might be 90. Stick a B773 in the lead, and it becomes maybe 90s and 100s respectively.

Surferboy
9th Aug 2017, 06:38
That's what regulations are for...


Because regulations have immediate effect? :ugh: And try explaining that to our 'customers' the airlines. :ok:

EastofKoksy
9th Aug 2017, 07:50
2 Questions:

1. Any change to landing rate and delay when a airport change from vectoring to point merge?

2. If ATCOs are sitting all day to monitor until **** happens, can the ATCO still provide reasonable service? I imagine if an atco is sitting in front of the machine for a few years and all of sudden he/she needs to provide conventional service or radar vectors, can the atco still provide a safe atc service?

2 answers:

1. Almost certainly no improvement
2. It will probably lead to the same de-skilling among ATCOs that has led to "the computers won't allow this aircraft to crash" mentality in some less experienced pilots.

It seems some posters are drinking too much SESAR Kool Aid!

Talkdownman
9th Aug 2017, 08:03
TDM, if you think you could remember
Not whilst coffin-dodging in Alzheimersville...
Happy to leave it all to you blokes in waistcoats and cravats. You're doing a grand job.
Gotta go, the nurse is coming...

Gonzo
9th Aug 2017, 08:15
Not whilst coffin-dodging in Alzheimersville...
Happy to leave it all to you blokes in waistcoats and cravats. You're doing a grand job.
Gotta go, the nurse is coming...

Oh my dear chap, that's not a nurse! :}

Up North Like
9th Aug 2017, 14:06
If you're cleared altitude is the platform altitude I.e 26L 2000ft you will be given 'cleared ILS approach'

If descended to something other than that such as 3000ft which we usually are, then you will be given 'when established on the localiser, descend with the glide path 26L'.

ZOOKER
9th Aug 2017, 19:19
"Oh don't sound so dreary about it...I think it's called "challenge".....;)"

Excellent post good egg........'Challenges' and 'Solutions'.......Top management 'buzz-words'.........I bet the phrase 'Going Forward' features in your vocabulary too....With monotonous regularity?

good egg
9th Aug 2017, 20:52
"Oh don't sound so dreary about it...I think it's called "challenge".....;)"

Excellent post good egg........'Challenges' and 'Solutions'.......Top management 'buzz-words'.........I bet the phrase 'Going Forward' features in your vocabulary too....With monotonous regularity?

Not so much Zooker...some folk are enthused by finding better/more efficient ways of doing things...others are satisfied to live in the dark ages. Depends on your viewpoint.

ZOOKER
9th Aug 2017, 21:43
Well, my viewpoint is trying to preserve The U.K's reputation as the best 'Global ANSP'.

Because, if EGLL keeps trying to squeeze 2 Quarts into a Pint Pot, one day it will go t*ts-up big time.......And our reputation as a 'Global Leader' will be gone.........Forever..

good egg
10th Aug 2017, 03:56
Well, my viewpoint is trying to preserve The U.K's reputation as the best 'Global ANSP'.

Because, if EGLL keeps trying to squeeze 2 Quarts into a Pint Pot, one day it will go t*ts-up big time.......And our reputation as a 'Global Leader' will be gone.........Forever..

If you don't squeeze 2 quarts into a pint pot you certainly won't be a 'Global Leader'...

Nimmer
10th Aug 2017, 08:07
"Global leader"!!!! I think we are behind already. The companies Innovation is good, however the development are implemention stages tend to be, shall we say challenging!!, (management speak).

Not having the staff to develop ideas is most definitely causing problems, resulting in under training, and implementation of equipment and procedures that are not fit for purpose.

Back to the topic, RNAV routes, point merge etc etc, will help the approach sequence, however ATC will never be just a monitoring job.

Why do we have inbound and outbound bulges of traffic, because that's when people want to fly. Airlines are not in the business of flying empty planes just to ensure ATC can sit back and monitor a lovely sequence.

Question on the vortex wake tool that was mentioned. This will obviously increase time between departures, how does that fit in with the current ethos at Gatwick of 60 movements an hour off the single runway???

DaveReidUK
10th Aug 2017, 08:43
Because, if EGLL keeps trying to squeeze 2 Quarts into a Pint Pot, one day it will go t*ts-up big time.......

It has long been acknowledged that, on average, there are around 10 days a year when Heathrow goes "t*ts-up big time" ("operations disastrously disrupted" in CAA-speak) and another 50 or so days when things don't quite get to that point ("significant but recoverable disruption").

pax britanica
10th Aug 2017, 09:52
All the plans re point merge etc will come to nothing unless the affected residents concerns are dealt with. LHR management do not seem to understand this , a couple of years ago they trial new departure routings causing an outcry in the affluent (and therefore influential outer suburbs around Ascot Camberley Bracknell areas. They never consulted people in these areas where there are lots and lots of inbound and outbound overflights but did consult people in places like Ashford and Staines which although theyare very much closer to LHR they are so close that nothing overflies them .

This project seemed similar to point merge with less vectoring and more planned 'fixed' approaches . removing the scattering effect of vectoring some people got almost every South/south west bound departure over them where previously it was just some. The latter was acceptable the former was not.

If point merge has similar effects you can forget introducing it because this part of the world to the west of LHR and West london to the east will just not allow it and both areas are inhabited by armies of lawyers , consultants and many airline personnel who can make more noise in Government circles than LHR can. And I woudl stress that many of them like em are not NIMBYS , they knew very well where LHR was went they moved to the area and it is a convenient and valuable asset. They dont mind a bit of noise but no one wants to be right under a fixed routing . So without an honest consultation with the neighbours you can forget any changes to LHR routings however clever.

An example of LHR and NATS management idiocy was arguing with member of the public at a large open meeting in Bagshot. They patronised and argued with the gentleman concerned until he revealed his occupation-BA A320 captain for 15 years -during which time he had flown god only new how many Midhurst and SAMPTON departures from LHR. Instant destruction of all credibiltiy of the proponents of change.

chevvron
10th Aug 2017, 09:59
All the plans re point merge etc will come to nothing unless the affected residents concerns are dealt with. LHR management do not seem to understand this , a couple of years ago they trial new departure routings causing an outcry in the affluent (and therefore influential outer suburbs around Ascot Camberley Bracknell areas. They never consulted people in these areas where there are lots and lots of inbound and outbound overflights but did consult people in places like Ashford and Staines which although theyare very much closer to LHR they are so close that nothing overflies them .

This project seemed similar to point merge with less vectoring and more planned 'fixed' approaches . removing the scattering effect of vectoring some people got almost every South/south west bound departure over them where previously it was just some. The latter was acceptable the former was not.

If point merge has similar effects you can forget introducing it because this part of the world to the west of LHR and West london to the east will just not allow it and both areas are inhabited by armies of lawyers , consultants and many airline personnel who can make more noise in Government circles than LHR can. And I woudl stress that many of them like em are not NIMBYS , they knew very well where LHR was went they moved to the area and it is a convenient and valuable asset. They dont mind a bit of noise but no one wants to be right under a fixed routing . So without an honest consultation with the neighbours you can forget any changes to LHR routings however clever.

An example of LHR and NATS management idiocy was arguing with member of the public at a large open meeting in Bagshot. They patronised and argued with the gentleman concerned until he revealed his occupation-BA A320 captain for 15 years -during which time he had flown god only new how many Midhurst and SAMPTON departures from LHR. Instant destruction of all credibiltiy of the proponents of change.

Nice one Pax

good egg
10th Aug 2017, 18:35
Nice one Pax

Although it depends where you put the point merge. If the 'point' of the point merge is at the latest point of the ILS where aircraft are normally vectored to then you get a spread of approach paths up until that 'point'. Beyond that point aircraft with fly the ILS like they always have.
However, if you place that 'point' miles and miles out then you will get an over-concentration of arrival flightpaths from there to touchdown.
It's hardly rocket science.

RNAV departures are slightly trickier....depends on the mix of routings and the amount of 'flyover' waypoints versus 'flyby' waypoints. By designing in more 'flyby' waypoints you get a bigger spread of departure routes....which is better for folk on the ground (less concentration of flightpaths because each aircraft takes a slightly different path, dependant on speed/weight/type etc.) even for the same RNAV SID.
However, not ideal for ATC in terms of 2 consecutive departures on same SID as each aircraft will fly slight variations on the same SID and therefore departure separation becomes an issue.
It's a good option if you can guarantee an alternation between say northerly and southerly departures all day long.

For the arrivals, if you had to have a point merge miles and miles from the airport (airspace limitations), you'd ideally have at least 2 routes to touchdown from the merge point....offering alternation (or 'relief routes') to residents on the ground.

Not always that simple though to design such structures. But certainly fairer to the communities underneath.

obwan
10th Aug 2017, 18:49
If you don't squeeze 2 quarts into a pint pot you certainly won't be a 'Global Leader'...


What a ridiculous statement

good egg
10th Aug 2017, 18:54
If you don't squeeze 2 quarts into a pint pot you certainly won't be a 'Global Leader'...


What a ridiculous statement

Not really obwan. Airports are demanding customers. If the ANSP you work for can't provide the necessary tools to assist ATCOs to meet these demands then the airport will look elsewhere....

kcockayne
10th Aug 2017, 19:07
But, the whole point of the saying is, that it cannot be achieved ! However, in the ATC environment, that is what you are seeking to achieve.......it can't be done.

pax britanica
10th Aug 2017, 19:48
Although it depends where you put the point merge. If the 'point' of the point merge is at the latest point of the ILS where aircraft are normally vectored to then you get a spread of approach paths up until that 'point'. Beyond that point aircraft with fly the ILS like they always have.
However, if you place that 'point' miles and miles out then you will get an over-concentration of arrival flightpaths from there to touchdown.
It's hardly rocket science.

RNAV departures are slightly trickier....depends on the mix of routings and the amount of 'flyover' waypoints versus 'flyby' waypoints. By designing in more 'flyby' waypoints you get a bigger spread of departure routes....which is better for folk on the ground (less concentration of flightpaths because each aircraft takes a slightly different path, dependant on speed/weight/type etc.) even for the same RNAV SID.
However, not ideal for ATC in terms of 2 consecutive departures on same SID as each aircraft will fly slight variations on the same SID and therefore departure separation becomes an issue.
It's a good option if you can guarantee an alternation between say northerly and southerly departures all day long.

For the arrivals, if you had to have a point merge miles and miles from the airport (airspace limitations), you'd ideally have at least 2 routes to touchdown from the merge point....offering alternation (or 'relief routes') to residents on the ground.

Not always that simple though to design such structures. But certainly fairer to the communities underneath.


Many thanks for the explanation of point merge. i can see that if the merge point was set 8-10 miles east of LHR for westerlies then the final approach will be very similar to today and no one on that segment will notice. But what about the arc that aircraft must fly down do all arrivals have to fly this in one direction or do you have a path for north arrivals or one for south. Either way it would seem that people further out under the arcs would get a greater concentration of overflights than exists today with the four stacks with different routings to a turn for final and that turn being started anywhere from 6-8 to 12 miles or more out.

Whatever the whole point of my comment was that if the airlines,airport and ATC providers do not work with the affected communities then they will be in for years of grief with objections court cases etc etc.

As regards departures the trial LHR did a couple of years ago meant that pretty much everything headed south or SW with LHR on westerlies was confined to one path toa point just beyond Ascot and then dividing into two one over Bagshot area heading for Midhurst and one passing just north of Camberley heading for SAMPTON and people in the area immediately after the split point got very very angry because traditonally differing performance and differing vectoring split these streams up once again,. With MID departures for example, some would make the turn south over Chobham Common but others would come out as far as Camberley before heading south and people have got used to that ,

good egg
10th Aug 2017, 19:50
But, the whole point of the saying is, that it cannot be achieved ! However, in the ATC environment, that is what you are seeking to achieve.......it can't be done.

And yet standards change. That's why we see enhanced TBS about to start at LHR.
Who'd have considered that possible a decade ago?
Zooker will no doubt bring me up on this, but by "challenging" previous assumptions, in this case wake turbulence, and proving that it can still be done safely, then efficiencies can be made.
Look at RECAT-EU...new studies, new technology, new efficiencies.

How many quarts did we fit in a pint pot 20/30 years ago? How many do we fit in that pint pot now? (If you need me to spell it out for you it is more!)

Whatever you think about 'the job' (in whatever business) - what it's about/what it should be about/etc, etc - these things change as technology evolves and parameters change.

Romanticising about the past is lovely but it's not reality...

kcockayne
10th Aug 2017, 21:00
I take your point, but surely there comes a point when you cannot squeeze any more in. Many would argue that point has already been reached. I agree that we squeezed more in years ago by exercising our ingenuity & pulling our fingers out - but we reached our limits, nevertheless. New technology & procedures can, undoubtedly, squeeze more in - but it will certainly reach its own limit. I would argue that this limit is finite & is fast approaching.

DaveReidUK
10th Aug 2017, 21:22
RNAV departures are slightly trickier....depends on the mix of routings and the amount of 'flyover' waypoints versus 'flyby' waypoints. By designing in more 'flyby' waypoints you get a bigger spread of departure routes....which is better for folk on the ground (less concentration of flightpaths because each aircraft takes a slightly different path, dependant on speed/weight/type etc.) even for the same RNAV SID

All of the RNAV SID trials at Heathrow over the last few years have involved flyby rather than flyover waypoints. That hasn't stopped communities complaining about the concentration of flightpaths. I'd suggest that the net flightpath variations between aircraft types on the RNAV SIDs are an order of magnitude less than those when flying traditional procedural SIDs (which is of course the reason the NPRs are defined as 3km wide swathes).

That's why we see enhanced TBS about to start at LHR.

Out of interest, what are the enhancements relative to the current TBS regime?

good egg
10th Aug 2017, 21:29
I take your point, but surely there comes a point when you cannot squeeze any more in. Many would argue that point has already been reached. I agree that we squeezed more in years ago by exercising our ingenuity & pulling our fingers out - but we reached our limits, nevertheless. New technology & procedures can, undoubtedly, squeeze more in - but it will certainly reach its own limit. I would argue that this limit is finite & is fast approaching.

Reminds me a little of "Team Sky" and the "aggregation of marginal gains"....

With each gain (e.g. TBS which, IMHO, was quite impressive) there are further opportunities to push those gains further (hence eTBS - although, personally I think there are bigger gains to be had with TBS than just LHR...).

Each breakthrough will be refined over time to become better than the first iteration.

The limits you talk about are surely only today's limits...based on what we know today?

Below is an excerpt from wiki (apologies) which demonstrates the point of progress and "limits" (setting limits, reducing limits and then increasing them again):

"The 1861 Act introduced a 10 mph (16 km/h) limit (powered passenger vehicles were then termed “light locomotives”). The 1865 'Red Flag Act' reduced the speed limit to 4 mph (6 km/h) in the country and 2 mph (3 km/h) in towns and required a man with a red flag or lantern to walk 60 yards (50 m) ahead of each vehicle, and warn horse riders and horse drawn traffic of the approach of a self-propelled machine. The 1878 Act removed the need for the flag and reduced the distance of the escort to 20 yards (20 m)."

And here we are in an age where we are seriously looking at driverless cars...planes too...some even question whether there is a future for human ATC.

IMHO that's a while off yet, but technology creep will get there, as will public acceptance...in time.

Gonzo
10th Aug 2017, 21:31
Enhanced time based separation scheduled for arrival early 2018 - NATS (http://www.nats.aero/news/enhanced-time-based-separation-scheduled-arrival-early-2018/)

eTBS stage 1 will bring the recategorisation (RECAT EU) of wake which will bring some reductions in separations.

It will permit wake separation to touchdown by taking into account aircraft speed profiles inside 4DME and runway occupancy times to predict compression encountered inside 4DME.

In essence, it will provide the radar controller with an indicator which shows threshold separation (wake or runway occupancy) + predicted compression. It will provide the tower controller with the threshold wake separation. Both controllers have the ability to see the other's indicator in cases of co-ordination.

Nimmer
11th Aug 2017, 07:56
All the plans re point merge etc will come to nothing unless the affected residents concerns are dealt with. LHR management do not seem to understand this , a couple of years ago they trial new departure routings causing an outcry in the affluent (and therefore influential outer suburbs around Ascot Camberley Bracknell areas. They never consulted people in these areas where there are lots and lots of inbound and outbound overflights but did consult people in places like Ashford and Staines which although theyare very much closer to LHR they are so close that nothing overflies them .

This project seemed similar to point merge with less vectoring and more planned 'fixed' approaches . removing the scattering effect of vectoring some people got almost every South/south west bound departure over them where previously it was just some. The latter was acceptable the former was not.

If point merge has similar effects you can forget introducing it because this part of the world to the west of LHR and West london to the east will just not allow it and both areas are inhabited by armies of lawyers , consultants and many airline personnel who can make more noise in Government circles than LHR can. And I woudl stress that many of them like em are not NIMBYS , they knew very well where LHR was went they moved to the area and it is a convenient and valuable asset. They dont mind a bit of noise but no one wants to be right under a fixed routing . So without an honest consultation with the neighbours you can forget any changes to LHR routings however clever.

An example of LHR and NATS management idiocy was arguing with member of the public at a large open meeting in Bagshot. They patronised and argued with the gentleman concerned until he revealed his occupation-BA A320 captain for 15 years -during which time he had flown god only new how many Midhurst and SAMPTON departures from LHR. Instant destruction of all credibiltiy of the proponents of change.

Chevron, pax Britannia, nimbyism in full effect. The counter argument is, until those residents accept that the Airport should be able to change its flight paths then ATC will remain in the dark ages. How long has Heathrow been there, when did you move :ugh:Pax?? The A320 captain would not of been smiling had someone who knew what they were talking about been at the presentation. :ugh:

Gonzo
11th Aug 2017, 08:08
Pax, what did this BA 320 captain say?

pax britanica
11th Aug 2017, 09:43
Gonzo

to be fair to the teams from LHR and NATs they ahd to deal witha lot of riduclous questions

Example-since the changes I am kept awake all night by aircraft noise -and of course LHR is closed at night essentially and one question often merged into another.

However the issue was that they claimed that people in the Bagshot area should not be too concerned as almost all aircraft would be at 6000 ft or higher. That of course isn't true -quite lot can make it up that high but even from my own observations many don't for all kinds of reasons. It wasnt so much they they were wrong- in fact rephrasing it a bit to say we aim to get planes up that high but probably exasperated by some of the sillier preceding questions, they got dogmatic on the wrong point and lost a lot of credibility over it.

Moving on to Mr Nimmer s comments I think I made it quite clear that most people in the area i live and that was affected by these trials are not in the least anti LHR -a great many of them work there and a lot of people see it as great convenience. In my own case I grew up next to LHR when it still had 5 runways so for me its always 'been there'. It is purely the point that people in todays world expect a degree of proper consultation about changes and not to be consulted as an afterthought which is what happened here. There was no consultation until after people complained in droves about changes in noise patterns. I cannot speak for those east of LHR but I suspect your argument holds much greater force but out to the south west i have never ever heard anyone complain about aircraft noise per se about LHR , EGLF is a different story, although I am sure there are complaints and enquires about odd incidents which usually have perfectly reasonable explanations which people accept.

GASA
11th Aug 2017, 11:01
All of these new technologies and developments are very exciting but as a controller at a busy unit, not Heathrow or Gatwick, my unit has not seen any advancements at all. So I've not been overly worried about technology creep degrading the job at my unit so far. Or am I wrong, are they planning to roll these things out company wide?

Gonzo
11th Aug 2017, 11:37
Pax, the problem is that the LHR RNAV trial was just that, a trial. I'm not debating the whys and wherefores, but should a trial have a full consultation? Interesting question. The trial was needed to gather data to determine how close together departure routes could be whilst still considered to be separated from each other. This could lead to respite departure routes in the future, but without trials to gather data they most surely will not happen.

A related issue was that Heathrow found, during the earlier 'Operational Freedom' trials, that people started complaining about them months before they had even started, due to the publicity put out by Heathrow.

Damned if they do, damned if they don't, in many ways.

The Fat Controller
11th Aug 2017, 14:00
This is an interesting read about what happened at Edinburgh when they had a trial of a new SID.

Edinburgh Airport flight path trial hailed despite complaints - Edinburgh Evening News (http://www.edinburghnews.scotsman.com/news/transport/edinburgh-airport-flight-path-trial-hailed-despite-complaints-1-4024539)

ZOOKER
12th Aug 2017, 20:25
good egg,

Apologies for leaving the frequency for a while, but it's an interesting debate, isn't it?

118.70
13th Aug 2017, 08:38
I'm not debating the whys and wherefores, but should a trial have a full consultation? Interesting question.

I'm not sure of the "full" - but if the airport wants to maintain any level of trust with the local communities and a sense of a social licence to operate it needs to have a meaningful engagement with the people it is going to affect in advance of inflicting significant changes from trial procedures. Noise effects need to be considered way beyond the 57dBA Leq16hr averaged contour.

http://teddingtontown.co.uk/wp-content/uploads/2014/09/heathrow-departures-trial-comments-categorised-20140921.pdf

pax britanica
13th Aug 2017, 10:36
118.7

exactly what i was getting at, involve and engage people early and you have much better chance of success rather than spending ages on the technicalities and preferred solutions only to find out no one likes them. And as you pointed out affected communities could be a good way from the airport and may not immediately come to mind as 'affected areas' in my experienced-having lived close to and around LHR for about 50 years people are very sensitive to change, most noise is a background issue unless you live at Hatton Cross or similar, and people are very sensitive to change if its time of day. loudness or pitch. In fact one of the problems is that comparing sound measured and perceived sound are often very different things

DaveReidUK
13th Aug 2017, 10:38
I'm not sure of the "full" - but if the airport wants to maintain any level of trust with the local communities and a sense of a social licence to operate it needs to have a meaningful engagement with the people it is going to affect in advance of inflicting significant changes from trial procedures. Noise effects need to be considered way beyond the 57dBA Leq16hr averaged contour.

Current CAA policy on airspace trials:

"Airports and air traffic control organisations sometimes carry out short-term trials to gather data and validate possible proposals for future requests for changes to the UK airspace structure.


This means that for a short period aircraft may be flying different routes to the published structure.
Government policy states that as these trials provide a valuable contribution to the efficient use of UK airspace we should encourage their use.

The policy also states that the organisation carrying out the trial is not normally required to carry out a consultation before doing so. But the Secretary of State’s policy does place an onus on us to consider the information the airport or air traffic control organisation gather on the environmental impact of a trial to establish whether a consultation/engagement is required. This will be based on information provided by the airport or air traffic control and take into account the level of environmental impact, the length of the trial and the environmental objectives given to us by the Secretary of State. If there is a consultation we will confirm to the airport or air traffic control organisation the level of engagement/consultation considered appropriate.

Due to the Secretary of State’s role in managing noise at Heathrow, Gatwick and Stansted if a trial is now proposed in the vicinity of these airports the organisation proposing the trial will also discuss the issue of consultation with the Secretary of State for Transport’s office.

Any trial will have a fixed start and end date and if, after the trial, the organisation running the trial wishes to make the change permanent then the full airspace change process, including consultation, will be required."

https://www.caa.co.uk/Consumers/Guide-to-aviation/Airspace/Airspace-structure-trials/

118.70
13th Aug 2017, 10:49
the Secretary of State’s policy does place an onus on us to consider the information the airport or air traffic control organisation gather on the environmental impact of a trial to establish whether a consultation/engagement is required. This will be based on information provided by the airport or air traffic control and take into account the level of environmental impact, the length of the trial and the environmental objectives given to us by the Secretary of State.Yes - unfortunately to date, the impacts have generally been assessed by the trial sponsors purely by the rough averaged noise contours and these are not sufficient to pick up the degree of annoyance felt by many communities suffering changed procedures. The latest airspace change policy consultation will hopefully move the goalposts to be more realistic and include wider noise metrics in the assessment.

Gonzo
13th Aug 2017, 18:36
I've got no skin in the game either way, but if there is a requirement to consult before a trial, then the overwhelming response will be negative. Human nature dictates very few people will welcome aircraft flying overhead them when none (or at least fewer) have before.

So if airport X consults on, for example, an RNAV departure trial, and 95% of respondants are negative, what happens? No trial? But maybe the CAA permits it anyway, due to the value of the trial to future developments, and then the community feels even more disenfranchised because of this.

I'm not sure of the "full" - but if the airport wants to maintain any level of trust with the local communities and a sense of a social licence to operate it needs to have a meaningful engagement with the people it is going to affect in advance of inflicting significant changes from trial procedures.

I think this is what did happen with OF trials, but as I said Heathrow were receiving noise complaints specifically referencing Operation Freedom trials months in advance of them actually happening. As you say, perceived noise/annoyance is often very different to actual noise levels, but the 'engagement' by the airport can heighten that perception of noise without any changes taking place.

It's not an easy situation to navigate.

118.70
14th Aug 2017, 06:50
My recollection is that local authorities were frustrated by the engagement for the OF trials.

Concerns expressed by local authorities regarding the trial

Communication about the trial design and reporting

10.25 Some local authorities expressed concern to Government and the CAA
about the little notice they had been given to inform or respond to local
residents before the trial – timescales which the CAA accepts were
largely outside HAL’s control. They also expressed a wish to be more
involved in the trial design. HAL made a commitment to local authorities
that if the Minister considered any components of the trial were
creating unacceptable disturbance to residents, then those components
would be discontinued.

10.26 Following Phase 1, it took time for HAL to assess what had been learnt
and to build that into the design of Phase 2 and gain approval from the
CAA and Government. As Phase 2 approached, local authorities were
again raising the same issue about being given insufficient time to engage
properly about the trial, despite the recommendations in the CAA report
regarding more engagement with stakeholders and through the NTKWG.
In some cases local authorities felt that they needed more information
to understand properly how some of the new measures would be
implemented, for example where they interacted with the existing night
flights regime.

10.27 When HAL produced its report on the summer season of Phase 2 in
December 2012, local authorities again complained that they were given
insufficient time to digest and comment on the draft. Local authorities then
expressed frustration that the early-morning arrivals measure proposed for
Phase 2 – which brought the prospect of reducing the number of flights
arriving before 05.00 – was not proceeded with, after it had been trailed
to residents. Local authorities questioned why it had not been established
earlier that airlines were unable to meet the operational requirements.10.31 Local authorities stressed to the CAA that they understood the
objectives behind the trial and sought wherever possible to explain
these to residents. However, they felt that if changes to established
operating patterns were to be accepted by local residents, they needed
open explanation, preferably in advance. The form of the data made it
more difficult for them to explain to a complainant why there had been
a particularly noisy aircraft a few days previously, and whether the flight
was part of the trial. They suggested that data could have been made
more accessible (such as a weekly narrative or a daily log listing flights
that landed out of alternation and the reason why), and that this would
have improved the understanding and trust of the local community.

10.32 A lack of explanation and transparency was felt to be a source of
frustration for residents and contributing to a climate of distrust. It was
suggested that it was of little comfort for local residents to be told that
the flight that had disrupted their sleep had been nothing to do with
the trial. These views reflect continuing issues around the wider
HAL-community relationship, rather than being specific to the trial itself.
https://publicapps.caa.co.uk/docs/33/CAP%201117%20Heathrow%20Airport%20Operational%20Freedoms%20T rial.pdf

DaveReidUK
14th Aug 2017, 08:42
So if airport X consults on, for example, an RNAV departure trial, and 95% of respondants are negative, what happens? No trial?

Carrying out a consultation doesn't necessarily involve offering communities a veto over whether a trial does/doesn't happen.

I think this is what did happen with OF trials, but as I said Heathrow were receiving noise complaints specifically referencing Operation Freedom trials months in advance of them actually happening

The OF trials were also characterised by a series of confusing and sometimes contradictory announcements by HAL about what they would/wouldn't involve.

For example communities were told initially that arrivals on 09R were part of the trial and then (following a prolonged spell of easterly operations) that, well, no they weren't actually.

It should be a no-brainer that consultation on any trials, whether at LHR, LGW or anywhere should require the sponsor to be unambiguous about what is planned to happen.

Gonzo
14th Aug 2017, 09:15
Carrying out a consultation doesn't necessarily involve offering communities a veto over whether a trial does/doesn't happen.That's excatly my point. Many of the community groups believe it does (witness the various groups protesting about the LAMP1A City RNAV routes, who claim that there was no consultation. When evidence is provided of the consultation, they come straight back and say that their responses were ignored), and thus if the hypothetical trial still went ahead, the relationship between airport and communities would probably worsen further.

How much would the publicity, how much would a pre-trial consultation, do to increase awareness and heighten the perceived noise annoyance?

118.7, I assume you've also read 10.15-10.24 and 10.39-10.44. In my direct experince with local authorities, they never think they have enough time! I'm not taking sides here, but there are many sides to every story.

One issue is that the OF trials were very complex, with several modifications to procedures being introduced simultaneously. It is sometimes not possible to exactly quantify the effect, or how the overall operation will change, when faced with such a complex trial. This was the point of the OF trial.

Maybe we should all start doing pre-trial trials, to find out the effect of the trial?:sad:

Not sure about you folks, but I'm very happy I've not yet written 'trails'. A pitfall the CAA unfortunately did not avoid in CAP1117! :}

pax britanica
14th Aug 2017, 12:53
having started the issue of consultations I should make it clear that I entirely understand how difficult the task is. I mentioned in one post how people came out with all kinds of ridiculous remarks , like complaints about things before they even started and flights al night long at LHR. I also think and agree that there should not be a need to consult before trials since the trials have to be done to get any sense of what might be workable . They should however be very clearly advised to affected areas and the airport should understand it is not only immediate neighbours affected.

Noise has lessened and lessened over time, a 787 descending towards Ockham over my house last night was barely audible and failed to make its presence known above a lawnmower half a dozen gardens away. But for all that there will be objections and complaints (although I understand that tiny minority of people make 75% of the complaints about LHR) and all i meant it is as well to be prepared for these rather than be in reactive mode or fine tuning proposals that might not be acceptable in practice due to public reaction-deal with the issue as early as possible because it will always take time to resolve

tubby linton
14th Aug 2017, 19:11
I am always surprised when I get taken on a Nats tour of SE England on a radar heading that a clearance limit is not specified. It may be in the Aip, but with the trend towards EFB and supplements, I will probably be approaching Penzance by the time I find it on the ipad.

Eau de Boeing
17th Aug 2017, 06:37
While we are on here, I have another Gatwick question.

Unfortunately I fly the world's biggest and ugliest aircraft on a regular basis into Crawley international and every time we do the aircraft behind us are always changed to an RNAV approach at the last minute, which I am guessing is because of the potential of the aircraft infringing the ILS critical area on 26L/08R??

On our LIDO (approach) charts it states that if we exit by certain points then we don't impact on this at all and 99.9% of the time you will see guys using "brake to vacate" and we can tell you not only exactly where we plan to exit, but also our runway occupancy time to the second.

At all other UK airports, this is never an issue as it seems to be communicated that we can exit long before getting close to the area so is there something that we are not aware of or can we help each other in minimizing last minute approach changes, particularly if it requires higher minima on a marginal day? Our regular approach speed at max landing weight is comparable to an A320 and we can stop and vacate in a short distance if required.

It used to be at LHR that Director or even London would ask at an early stage where we planned to vacate to help planning and we have normally selected an exit long before even getting into UK airspace and we will always advise if we need a longer than normal length to vacate, it is just knowing when to put this into conversation.

Would be interested to get some feedback on this to hand back to fellow dugong drivers.

Cheers
EdB

tubby linton
17th Aug 2017, 11:20
How would you expect to receive a clearance limit on a radar heading?
In other countries (Brazil?)I believe they give a radial from a VOR

Del Prado
17th Aug 2017, 14:02
While we are on here, I have another Gatwick question.

Unfortunately I fly the world's biggest and ugliest aircraft on a regular basis into Crawley international and every time we do the aircraft behind us are always changed to an RNAV approach at the last minute, which I am guessing is because of the potential of the aircraft infringing the ILS critical area on 26L/08R??

On our LIDO (approach) charts it states that if we exit by certain points then we don't impact on this at all and 99.9% of the time you will see guys using "brake to vacate" and we can tell you not only exactly where we plan to exit, but also our runway occupancy time to the second.

At all other UK airports, this is never an issue as it seems to be communicated that we can exit long before getting close to the area so is there something that we are not aware of or can we help each other in minimizing last minute approach changes, particularly if it requires higher minima on a marginal day? Our regular approach speed at max landing weight is comparable to an A320 and we can stop and vacate in a short distance if required.

It used to be at LHR that Director or even London would ask at an early stage where we planned to vacate to help planning and we have normally selected an exit long before even getting into UK airspace and we will always advise if we need a longer than normal length to vacate, it is just knowing when to put this into conversation.

Would be interested to get some feedback on this to hand back to fellow dugong drivers.

Cheers
EdB

The following aircraft should be told more or less on first contact with gatwick if they are to expect an RNAV approach rather than 'at the last minute'! ;-)
I don't think it's really a problem for the following aircraft except on the very rare occasions when weather precludes an RNAV and a 20 mile gap is required.

On the subject of speeds, are you expecting 160 to 5 or 160 to 4?

Eau de Boeing
17th Aug 2017, 14:58
Happy with either, unfortunately company stabilisation criteria require that we are at landing configuration at appropriate speed by 1500' agl and if not by 1000' with a couple of caveats then we have to fly a G/A. Therefore any tighter than 160 to 4 can get interesting with a tailwind.

Normal approach speed is in the region of 130-135 kts so we actually have a bit to lose from 4 miles for a "big jet".

I was just curious why it was necessary in the first place to give the following aircraft the RNAV approach if we are not likely to infringe the ILS on a normal day out.

Anything after my last coffee of the day onboard is last minute ;-)

Ratatat
17th Aug 2017, 16:27
Eau de Boeing

On 26L ops I have only seen a 380 vacate at anywhere other than the end on 2 or 3 occasions since they began operating. I am obviously not there every movement but am sure 95% + vacate at Juliet.
The effects on the ILS - I have seen an aircraft established on the ILS at 10 miles when the 380 turns off the runway at Juliet. The deflection in the ILS caused it to deviate 1.5 miles to the north.
Have not seen the effects on 08R where 99.9% vacate at BR.
Why such the low numbers of vacating at FR? Excellent runway utilisation when I have seen it done, meaning no lost movements. Whereas vacating at Juliet means 2 lost movements.

Regards

Smokey Lomcevak
17th Aug 2017, 16:58
Lost 2 movements yesterday. U2 following had to bin it when EK rolled to Julliet (as they said they would when asked by LGW Tower) with one lined up from Alpha. When asked to expedite, the chaps said they had a speed limit once within the stop-end. Skip and I mused that perhaps that wouldn't have been an issue if they were able to avoid using said stop-end.

I do remember being told by someone that brake temps were an issue as the turnarounds are relatively short.

It's worse in LVP's. 27nm gap required apparently.

Eau de Boeing
18th Aug 2017, 03:42
Let me explain a little further and it should clear it up for you.

08R works well for both of us. You get 99.9% exits at BR and a guaranteed runway occupancy time every time. The distance from touchdown to BR means we can vacate, taxi into stand 110 and keep our brake temps below 300 deg, which is the optimum for the relatively short turn-around in Gatwick.

On 26L however it can be a bit more problematic.
Firstly there is the issue of runway exits, for the A380 only FR and J are available to us.
In simple terms, we have a choice of either vacating at J, which gives us the option to vacate direct onto J and then manage the brake temps well for the outbound crew.

OR

We vacate at FR and our brake temps will normally be around 450-500 deg by the time we get on stand. With no external cooling other than the Sussex breeze we tend to lose 100-120 deg an hour from the brakes and we have no brake fans fitted. Max permitted temp for take off is 295 deg and we require brakes to manoeuvre around Gatwick on the way out and normally have quite a wait at the holding point.

Now this is not your problem I appreciate, but it is an important consideration. When I am training guys and we are early then I encourage guys to use FR and try to manage the temps accordingly and also it gets me to Tesco 5 mins earlier. However I cannot speak for everyone.

Now for Smokey Lomcevak's bored musings with his "skip", the issue with the end of the runway is with our OANS/Airport Nav/ROW/ROP systems, of which I am sure he is an expert.

The layout of the airport at Gatwick means that "J" lies beyond the official end of the runway, which means that if we are doing more than 10kts past that then there is a high likelihood of a Runway Overrun warning (not good) and subsequent ASR paperwork. The BTV system targets 10kts groundspeed 300m from the threshold end so guys need to disconnect it early to allow the plane to roll on at a higher speed.

So in short on 26L, FR is ok on a normal day but gives us high brake temps for a turnaround. With being unable to accept any other exit after that until J, we are almost stuck between a rock and a hard place.
If the airport surveyed G/GR then it would probably make all the problems go away instantly for both sides.

However you are more than welcome to ask the question about vacating at FR and I am sure most "skip's" (out here we are called captain) will happily oblige. The key thing is to ask early to give us the chance to re-select the exit during a non-critical stage of flight. On transfer to tower it is a bit too late to manage it with someone inexperienced on type, which is why most people will take J.

In return if we can get an accurate TOBT/TSAT and minimal taxying, then most people will happily dispatch with higher brake temps, especially on 26L.

I am happy to give any interested controllers a tour of the plane and associated systems next time I am in Gatwick (next month). We did this in Birmingham, after starting operations there and I think it was mutually beneficial for both sides. Feel free to PM me.

Ratatat
18th Aug 2017, 07:13
Thanks for the info. All very helpful. Will pass it along the line.

Smokey Lomcevak
18th Aug 2017, 12:48
EdB,

Thanks a lot. Sounds like most of the stuff I've heard is spot on.

Very rarely do I experience boredom sitting at A3, especially with you big boys coming in, and occasionally we resort to humour to fend it off. If that doesn't work, I simply remind myself that I'm earning cash every minute I'm sitting there!