LHR Speed Trial
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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.
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.
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.
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.
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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.
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.
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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.
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.
Originally Posted by eyeinthesky
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.
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.
Assuming they're read, of course!
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Originally Posted by eyeinthesky
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.
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!
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Originally Posted by CAP493
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
Thanks, Does it seem to be meeting expectations?
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No bites? 
Bugger, you Civvies are hard to wind up after all.
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!
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
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.
Bugger, you Civvies are hard to wind up after all.
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!
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
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.
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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.
)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.
ECON cruise, LR cruise...
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...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...
Coat, tinhat, door...
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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!
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!
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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...
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...
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[QUOTE=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...[/QUOTE]
What!! Surely they should be alright as long as they don't have to park the thing
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...[/QUOTE]
What!! Surely they should be alright as long as they don't have to park the thing
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]