LHR Speed Trial

[doo]

How much longer is the speed trial to go on for?
What is the purpose?
Thanks

[CAP493]

If you're referring to the departure speed trial currently ongoing for departures from six LTMA airports/airfields (LGW, LHR, LTN, LCY, STN & NHT) i.e. not just LHR, its purpose is to determine whether or not ATC handling can be improved by not lifting the 250kt speed limit below FL100, and therefore, airspace capacity can be increased.

With Gatwick, Heathrow, City, Luton and Stansted all now handling record numbers of flights it's important to safely squeeze every ounce of capacity out of the existing controlled airspace, given the protracted and painful process involved in extending it.

:8

[Someone_Else]

It is scheduled to run for 90 days from when it started - 7th April.

[Turn It Off]

So it runs till the 97th of April yeah?

[chevvron]

I thought it was a general speed limit in class A below FL100, not just for the major airfields, not just for departures.
No I was wrong. Found the AIC; it's Yellow 201. Trial is for 90 days from 8 Apr 06. Daft thing is it says 'airfields outside CAS do not need to cancel speed restrictions before giving traffic to a TC sector'! But there's a speed limit of 250 in class G anyway which airfields are NOT allowed to cancel.

[Dizzee Rascal]

It says: "Aircraft departing on SIDs from London Heathrow, Gatwick, Stansted, Luton, London City and Northolt or joining LTCC airspace from airfields beneath or adjacent to it, are required to observe an IAS limit of 250 kts below FL 100".


I thought there would have been a NOTAM issued regarding this, I can't find one. I doubt the foreign operators (which operate in to the place I work at) look at the AIC's as regularly as they do the NOTAMs.

[eyeinthesky]

QUOTE
I thought there would have been a NOTAM issued regarding this, I can't find one. I doubt the foreign operators (which operate in to the place I work at) look at the AIC's as regularly as they do the NOTAMs.
UNQUOTE

Why would you need a NOTAM issuing which tells you that the rules are to be complied with?

The lifting of speed restriction has always been at ATC discretion. The standing rule is max 250kts below FL100 on departure, so there is no change in the rules.

[spekesoftly]

Why would you need a NOTAM issuing which tells you that the rules are to be complied with?

The lifting of speed restriction has always been at ATC discretion. The standing rule is max 250kts below FL100 on departure, so there is no change in the rules.
Fair point, but if the 250kt speed restriction was frequently cancelled by ATC in the past, then might not a NOTAM reduce the number of "Any speed?" calls from pilots?

Assuming they're read, of course! ;)

[Dizzee Rascal]

Why would you need a NOTAM issuing which tells you that the rules are to be complied with?

The lifting of speed restriction has always been at ATC discretion. The standing rule is max 250kts below FL100 on departure, so there is no change in the rules.

True but for the last 10 years (or thereabouts), the first contact with a TC sector on departure has been c/s climb to altitude **** ft, no ATC speed restriction! Pilots would become to expect it, just like they came to expect the sqawk ident reuqest on first contact with TC and then automatically did it before the request, a NOTAM was issued for that.

Heard a foreign a/c which departed my place on Thursday ask TC if there were any speed restrictions, (he had been restricted to do 210KT on his departure as the radar guy had a/c all over the RVA). I heard the TC guy tell him standard speeds and I watched him promptly accelerate to 310KT ground speed at 4000ft with someone at 5000ft which he went underneath a few miles up the road.

Just thought that if this guy had seen a NOTAM (or the AIC) he might have adhered to 250KT IAS and got a climb a bit sooner on.

Of course, I do know that his IAS could have been 250KT!
:)

[doo]

its purpose is to determine whether or not ATC handling can be improved by not lifting the 250kt speed limit below FL100, and therefore, airspace capacity can be increased:8


Thanks, Does it seem to be meeting expectations?

[A good headin]

250kts below FL100? How do you civvies cope with aircraft that fly so slooooooowly?
I know I'll get me coat, again;)

[A good headin]

No bites? :ugh:

Bugger, you Civvies are hard to wind up after all.:bored:

Where's my chum 'Heathrow Director'?

He is really cool and used to do the same job year after year (yawn) with Dir N and S and everything doing less than 250kts below FL100, pure luxury!:p
My wife could do that!:}

PS. I heard LHR had an aircraft overshoot last week and 'Heathrow Director' had to come out of retirement to provide his expert advice on what to do.
Zzzzz:zzz:

PPS. This baiting is only aimed at 'Heathrow Director' and is not aimed at the real controllers at LHR who who a damn fine job.:ok:

[Bright-Ling]

Not a bite - but as you no doubt are aware, the speed trial of 250kts is to ensure more aircraft can use the skies. (Sector overloading rare in the MASOR!!!:) )

Also, HD's chums only work some dep's on Easterlies.... so it doesn't really apply to him.

Anyway - civvy ATCOs spend are too busy counting there money to worry about the 4xship and Towline.

[Empty Cruise]

...and if the AF didn't need so much airspace practising for the next invasion of some oil-rich country, we could accomodate even more planes :}

Coat, tinhat, door...:cool:

[Gonzo]

Sorry, what was that Empty Cruise? Didn't catch it...I was deciding how to get to work tomorrow, the helicopter or the Aston.......:confused:

[REVOLUTION]

Unless i'm mistaken I don't think this speed trial is to increase sector capacity.
I was under the impression it was to cut down on 'bunching' of LTMA outbounds. Also from a safety point of view aircraft flying at slower speeds are more manouevrable etc.

As a LTMA controller I have found that because aircraft are flying slower they remain in the sector for longer so you actually end up talking to more aircraft at any one time.

Despite what people may think, before this trial we didn't always lift the speed restriction on every aircraft. Being able to keep an aircraft at 250kts or allowing it to speed up is a useful tool that we no longer have at our disposal.

I also do one of the TC 'feed' sectors and have found at higher level this trial has made absolutely no difference and we still need to put aircraft on parallel headings to maintain seperation.

Aircraft such as 747's need 270kts minimum which we permit. This though means if left they will catch the preceeding aircraft that is flying at 250kts (We obviously don't allow this to happen, by accelerating the ist aircraft or by using headings etc.)

Just a few personal observations!

[Empty Cruise]

The Aston, Gonzo - take the Aston... :D

[Cough]

It strikes me that (as a driver) to increase capacity then you need to apply variable speed limits in the same way that you do for arrivals. ie. for the first a/c in a bunch give him a min 320 knots and progressively less for the rest. Most drivers that I know wouldn't have a problem with this (conditions permiting of course) and it would achieve the aim i.e. to avoid bunching.

Having a fixed speed limit for most (ATRs and DC10's/Jumbos excepting) just delays the problem till later, coz the second you get above FL100 the everyone is at a different speed.

Thats just me thinking about it anyhow. Would love to hear how its actually going...

ooh just thought. Many A/C have bird speed limits which may limit things below FL80...

[Lookatthesky]

It strikes me that (as a driver) to increase capacity then you need to apply variable speed limits in the same way that you do for arrivals. ie. for the first a/c in a bunch give him a min 320 knots and progressively less for the rest. Most drivers that I know wouldn't have a problem with this (conditions permiting of course) and it would achieve the aim i.e. to avoid bunching.
Having a fixed speed limit for most (ATRs and DC10's/Jumbos excepting) just delays the problem till later, coz the second you get above FL100 the everyone is at a different speed.
Thats just me thinking about it anyhow. Would love to hear how its actually going...
ooh just thought. Many A/C have bird speed limits which may limit things below FL80...


What!! Surely they should be alright as long as they don't have to park the thing :}

[Dan Dare]

As a fluid dynamicist I'd have thought that you increase capacity by increasing the speeds. For a fixed volume of air the best way to increase the mass flowrate through that air is to increase the velocity. If everyone flies at 350kt then there are more 1000' or 3nm to go around and everyone is happy! [/toungue in cheek]

[Jerricho]

Forgive my fuddled brain, but isn't it normal practice for one of the departures of Gatwick to keep the speed restriction to reduce the radius of turn due to the proximity of airspace boundaries? Could also be said for Heathrow CPT departures on Easterlies.............smaller radius of turn for the departure, more room for downwind traffic on the outside (of course, if it's an A340, forget it)

[Over+Out]

Big turns, keep the speed restriction on.
I cannot see any advantage in a restriction on ALL aircraft. give the controller the tool to be able to use the speed of the aircraft to his/her advantage.
This trial does nothing to improve bunching and may well give the TC controllers more workload.

[anotherthing]

As a TC ATCO I am a bit miffed that the trial says we should not take the speed off. Speed should be a tool we can use to help with departure separation from several adjacent airfields.

Having some shiny a:mad: :mad: ed git who is sitting in an office somewhere, not having controlled for x amount of years telling me how I should do my job is a bit galling.

Selective use of speed, headings etc etc is how an ATCO operates and should not be meddled with. I know from trying that ifI leave the speed restriction on every departure as the trial dictates it causes worse bunching than taking speeds off selected aircraft.

It does not take a brain surgeon to work that one out.

The office workers should wander off and design some more swirly stripes... "The Logo signifies separation and flow" and the changing colours represent "diversity" my a:mad: :mad: e!!

[Gonzo]

anotherthing.......

I am a bit miffed that the trial says we should not take the speed off

But then what would be the point of the trial? :confused:

Guys, it's a trial, so adhere to the terms, and make sure you submit your experiences, so that when the trial ends, there is evidence you can point to while saying 'it'll never work!'

[BEXIL160]

Having some shiny a ed git who is sitting in an office somewhere, not having controlled for x amount of years telling me how I should do my job is a bit galling.


It would be a bit of a shame then if it came from an operational TC ATCO who sometimes works in an office ;) ;)

As Gonzo says, quite rightly, it is a trial. Setting out to prove it doesn't work only proves you never tried. To get evidence, you need to adhere to the terms.

One thing that has happened in the past, and was a cause for concern was removing the speed restriction as a matter of habit, rather than having a good separation / presentation resaon for actually doing so.

Best rgds
BEX

[Lookatthesky]

And the trial is a pre-cursor to "the future" when we shall have P-RNAV outbound routes, separated by speed/departure intervals.

It will all be over soon :ok:

[Point Seven]

Gonzo

I must remember those words the next time we have a trial that you don't like...:p

Single conditionals anyone..?

P7 (shiny a:mad: :mad: sed git)

[Jerricho]

Who the hell woke you up P7??? :p

[Gonzo]

Fancy a bit of fishing, P7? :E

Poor attempt, mind you. we both know it.

[anotherthing]

Bexil

I am adhering to it (when it is safe), hence the reason why I know it does not work.

I agree that some ATCOs remove speed as a matter of course - it should be selective.

LookatTheSky

Unless EGLL, EGKK, EGWU, EGSS, EGLC and the other airfields that pump out DVR departures introduce a system whereby they integrate all there departures, I do not see how the PR-NAV oputbound routes will work, we will still have bunching.

Any such co-ordinated departures will surely severely hamper the busy airfields operations and reduce the number of departures??

[scoby]

I am adhering to it (when it is safe), hence the reason why I know it does not work.
I agree that some ATCOs remove speed as a matter of course - it should be selective.

anotherthing, please enlighten us - when is it UNSAFE to leave the speed restriction on?

I'm getting a bit narked with two things - first, TC ATCOs who claim to have always used speed control on departure as a 'separation tool' - rubbish, everybody used to cancel the speed on first contact as a matter of routine. Secondly, there are those who seem to think that cancelling the speed restriction somehow maintains or creates separation between aircraft. How exactly?

There is a good argument that if aircraft are flying at a uniform speed, the potential exists for a more orderly output. It relies on the ATCO playing the game of course (and it seems to me that there are few TC ATCOs who have bought into this one). If this weren't the case, then shouldn't we tell approach controllers to sequence their aircraft onto the ILS whilst permitting the pilots to fly whatever speed they fancy?

Imagine a hypothetical situation where all aircraft below FL100 had to fly at 250Kts, and that this were the way it had always been (I believe that this is the case throughout the USA by the way, and they seem to have few problems with it). If a dictat had then been issued telling TC controllers to remove the speed restriction for all aircraft on departure, there would have been uproar at the potential safety implications........

[wizad]

well im one of the ones keeping to this trial... about 93% of the time. the only time ive cancelled it is when 3 mins on deps such as successive midhursts or dovers (easterlies) are just a little closer than im totally comfortable with. most likeley because the second aircraft is flying faster than he should and not requested/reported it.
to be honest id rather go back to having the choice of cancelling the speed as my tool. but although this trial has introduced new conflicts, it does help in other areas where catch ups were a bit of a problem. i gave 3 aircraft on sams to hurn all on the same heading in trail climbinmg to FL150 about 7 miles apart a piece.... but are pilots now becoming all to aware of this trial and flying faster anyway???
if this trial makes us aware of possible plus points of keeping the speed on then its working, but we should still have the choice as ATCOs.
oh, and is anyone brave enough to photocopy the speed trial comment book in the ops room and put a couple of the less offensive but rather entertaining entries.... the letter to michael o'leary has raised a few smiles.

[Not Long Now]

I must say I tried to keep to the trial to start with, but when busy, old habits die hard and I often found myself getting to the " no speed re.." before developing a bit of a stutter and having to decide wether I could be bothered to stop myself.
Anyway, as far as I'm concerned, it hasn't improved things any, but then has it made it any worse? Well, yes and no.
When we cancelled the speed routinely, we knew what problems may arise, because that was what we were used to, i.e. B757 ( and lately Dash8-400) immediately started catching the one infront, Swiss never accelerated anyway, Tarom would be doing Mach 3 in about 3 seconds etc etc.
Now however I have almost been caught out three times because of sudden drastic reductions in rates of climb as a/c start to accelerate passing 100. Planes doing 2.5/3000 fpm suddenly drop to about 500fpm as they go through 100. Also heavies, particularly gulf operators in 777s it seems, when they have been level at 6000 for some time and are given climb seem to take for ever to get going, often remaining level for nearly a minute (it seems, probably a bit less I'll grant you) and requiring me to go back and confirm clearance.
Is this a better or worse situation than catch ups?
Well probably about the same, BUT with catch ups etc, we knew they would happen and were to some extent expecting it so had a plan B and even C because that was what we had been trained with and were used to. I dare say in a few months time we'll all be used to the new problems that arise, but those months could well be uncomfortable.
It's another rule someone thinks will help somehow, and may well do in the future, but for now, I've given up. Maybe that makes me a bit hopeless, but I've got to the stage where too many people are trying to tell me how to do the job I was trained to do and they weren't, so it's my license and I'll do with it as I please. And as for informing all the operators so no pilots will be questioning any speed, well now that is a joke.

[anotherthing]

Not Long Now

Good post, my sentiments exactly.

The one good thing to come out of the trial is that it will hopefully stop ATCOs automatically taking the speed off every departure and make them do so more selectively.

However, we should still retain the right to use speed as a tool for controlling.

As you mentioned regardig climb rates etc, it can cause a few sticky moments when you go for a climb through based on perceived climb rates, just to see the rate suddenly fall off. Not ideal when this is part and parcel of working in a busy TMA environment!

[doo]

Thanks to everyone for their input.:8

From the other side i.e. 320 pilot flying to and from LHR for many years, yes after tooting along @ 250kts for longer than previously I now hope for quick climb so I can break FL100 and speed up, and yes that kills the climb rate.
Previously whith the speed lifted there was the option to force the bus up( it likes to respond slowly) by trading the increased speed for climb rate, now that option is gone, so there is the possibility of slow climbs from the buses.

[anotherthing]

doo

I do not know what sectors you fly, but as a pilot operating from LHR, you will no doubt realise that to get climbs in, we need to take you off the SID when we can (leave epsom on a heading etc etc), otherwise you end up flying under the stacks at 6000', with Gatwick SIDS stuck below you, and London City et al stuck below them - it can become a bit of a nightmare.

If we are too busy, or need a bit of a break from monitoring A/C that are not on the SIDs (it does get tiring because that in itself causes some new problems(); the speed limit imposed means that you will, unfortunately, take longer to clear the holding areas therefore it will take longer (in time, not track miles) before we can climb you.

The trial has its good points - i mentioned what I think is the main one in my post above, about selective use of "no speed restrictions", but it does throw up a lot of new problems, especially when you are dealing with multiple airports with interactive SIDS!!

[Lookatthesky]

Not Long Now
Good post, my sentiments exactly.
The one good thing to come out of the trial is that it will hopefully stop ATCOs automatically taking the speed off every departure and make them do so more selectively.

This, however, was not the point of the trial! although I agree with your sentiments

[wizad]

so apart from the 'unofficial comments' book in the ops room, has anyone been asked how its going so far by management? or are their eyes closed to how these things affect us.
heres a thought.... lets stick our noses into their work and things that we dont really know much about, change it all round to what we think will work and make them do it?

[anotherthing]

Lookatthesky

No it was not the point of the (ongoing) trial, but if the trial makes us more selective in our use of "no speed" it's no bad thing.

It has made me more selective and although I am no longer following the trial to the letter (not out of sheer bloody mindedness, but because if i left the speed on everything it would cause bunching and also make my job more difficult); it has made me think more about my use of the phrase. :)