View Full Version : 250kts on departure

17th Jan 2006, 10:00
Just a quick straw poll, as the London TMA controllers are more than likely going to have to trial operations in March whereby we cannot take the 250kt speed restriction off you guys until you are above FL100.

This trial is supposedly going to stop aircraft 'bunching' at exit points (though how that will work when talking about 4 different major airports launching A/C independantly to the same exit points is a mystery to the coalface ATCOs)

The question I have is - our management, who are forcing this trial on us, inform us that the airlines have been informed....... to what extent do you guys know about this - or is it the case of both sets of management have agreed to the trial but not told the coalface workers??

What are your thoughts on this restriction?

17th Jan 2006, 10:03
I think those new chunky new pit-props supplied by the management might just be made of balsa-wood.

17th Jan 2006, 10:08
Does this still allow acceleration to clean speed (usually 280kts for a heavy -400) or is it going to be an across the board restriction.

17th Jan 2006, 10:09
never heard this recently (in the past year at least) to be honest unless you have a huge transit accross the TMA (eg towards dvr from the north and its busy) it does not make a huge difference time wise (max 1 mniute i reckon) so all in all if its the flow and possible reduction in being kept low or holding on arrival then it can only be a good thing.

Just to iterate - NO

The Real Slim Shady
17th Jan 2006, 10:10
May have some effect on the heavy jets wich prefer a high speed climb to clean up, but just means we, smaller twins, get to 100 sooner if we have to stick to a 250 limit.

17th Jan 2006, 10:39
(though how that will work when talking about 4 different major airports launching A/C independantly to the same exit points is a mystery to the coalface ATCOs)

It shouldn't be.
Tactical VECTORING, not too dissimilar to approach radar methods, is the answer. At 250 kts you'll find aircraft a lot more "manoevrable" (they cover less ground in turns for instance).
AREA people have to do this in the UK and abroad (with varying degrees of success) daily. e.g. streaming into MAY, AVANT, DPE, MURUE.... corner posts etc , all from different points.
Haven't got "time" to do it? Split the sector. Give yourself more time. You may be surprised what is achievable.
Best Rgds
a coalface ATCO

17th Jan 2006, 10:41
Haven't heard a thing from my lot...(BA)

17th Jan 2006, 11:09
It's standard SOP in the US, at least at every major airport I've ever operated into or out of. Never been given "no speed restriction" below 10,000' when arriving or departing from an airport over there.

With reference to the 'heavy' jets requiring greater than 250kts min clean speed, I've never had any ATC restrict us to the 250kts on departure. On the B744 at typical T/O weights before an Atlantic crossing, our min clean speed will be around 260-275 knots. We always climb at 250 or min clean, whichever is greater. Occasionally, ATC may want to know what our min clean speed will be for their own decision making reasons but invariably, they are well aware that a heavy a/c will be slightly above 250kt min clean.

As has been pointed out already, the typical time difference of reaching a boundary or entry/exit point between 250kts and 300kts is around one minute or less depending how quickly you can reach 10,000'.

Thoughts on the restriction? Won't really make much difference. What is preferable is more direct routings.

17th Jan 2006, 11:16

Thats the worry we have, that you guys flying the aircraft have not yet been told. So unless you do, we are going to be hit with the 'can we accelerate yet' question all the time.


We do not have the time nor the space ... you should know that because of the way that we are presented with traffic running into Heathrow and Gatwick from the south (as your name implies you know this area). We often get traffic running abreast and certainly not streamed. Lets not turn this into a Swanwick/TC bunfight. The bunching will happen regardless of initial speeds. If the anticipated result is aircraft in one nice stream - it's not gonna happen. A/C will climb quicker, but we rely on knowing that certain aircraft will be very fast a 6000' so that we know they will clear the holding areas and be free to climb sooner.

As for Tactical vectoring - I think you will find we kinda know how to do this at TC due to the multitude of crossing tracks; but both you and I digress - the original post was to find out what the guys and gals at the other end of the Mic thought and also to find out if they had been told anything yet because our managment assures us they have.


The acceleration of A/C to clean up has not even been addressed - beyond the managments limited brainpower to realise the implications of letting some guys accelerate to clean up and the new separation problems that will pose... only so much vectoring we can do if you are stuck under the stacks and there are departures from Heathrow and Gatwick climbing to the same SID level, going to the same point!

Taking away these sorts of tactical tools form the coalface worker is another management interference and proves how little todays managers understand the coalface workers problems.

Eager Beaver

It won't help flow, it just means that A/C will get to the fix a minute or two later... airports will still be firing them off at the same interval - restrict that and you will benefit flow.

It is only for outbounds, it will have no impact on holding arrival. If you are going to hold, you will hopefully have been instructed to slow down before then anyways - usually as soon as you have level separation from any other A/C running in alongside you and you have met the level by restrictions.

You can't really restrict speed much more before then as the en route area guys (like Bexil) need the speed to make sure you get the height off, and to start implementing spacing as they usually get you in a bunch from the French.

We also need to make sure you get the height off to have you in levels which are separated from all the other holding areas.

Slim Shady

If we can get you in the clear to climb we will, then as you say, you can accelerate. So the 'natural separation' we have with different A/C types is also being taken from us to a certain extent!


That is exactly the point - it won't make much difference so why complicate matters? We are going to have some aircraft accelerating to get clean others doing 250kts, then the A340!!

Direct routeings are more the realm of the en-route guys - they have to sort the rubbish we throw at them before they can start doing that for you!! Tho if its quiet we will try to send you direct, but in a lot of cases it does not comply with En-routes separation requirements regarding parallel routes.

What galls us is the fact that our tactical tools are slowly being eroded by management

17th Jan 2006, 11:17
personally when departing heathrow and being held at 6000ft I am happy to be allowed to speed up to get away from the heathrow holds but I do not have the big picture and I am happy to comply with any reasonable request to help everyone on their way. Lets also bear in mind that most bird strikes occur below 10,000 ft and the cockpit windows are not tested for bird strikes at 280 kts.
Safe flying everyone :ok:

Captain Airclues
17th Jan 2006, 11:28
In the US, ATC are not allowed to cancel the 250kt limit below 10,000ft. However, the restriction does not prevent you from flying at minimum clean speed. FAR 91.117(d) states; "If the minimum safe airspeed for any particular operation is greater than the maximum speed prescribed in this section, the aircraft may be operated at that minimum speed".

17th Jan 2006, 11:30
Whilst it is nice to be able to speed up it really does not actually make a lot of difference from my point of view, saves a fraction on time and fuel but not enough to matter. I would have thought that it makes more difference in flow control for ATC to be allowed to speed aircraft up so you can give the guy at the front of a queue of other aircraft a bit of a lead.

Giles Wembley-Hogg
17th Jan 2006, 11:37
Worth bearing in mind for the TC people that "expedite" may not yield as high a rate of climb as previously if we are kept at 250kts before we climb.


17th Jan 2006, 12:06

Yep - point taken however a lot of the time we keep EGKK Lam Deps at low speed - this helps them outclimb the Biggin stack and also means the radius of turn is smaller as it is less of a turn back to keep you clear of EGLL traffic inbound from the north east. (And turn radius is less)

That is us using speed as a tool - we are about to be denied using speed as a tool in different ways for different A/C.

Just to clear that up GWH as it may seem we are talking at cross purposes, I understand your true ROC may be less, but in ATC terms, although we may want a high fpm rate, what we are looking at in reality for us is your actual feet per mile rate. When you have accelerated, we are still judging your climb rate on how far away your traffic is.

We both want a good climb at times, but interpret it in different ways!

17th Jan 2006, 12:11
After a season on the north american continent i no longer see any need to accelerate past 250 below ten , going up or down, unless specifically requested. Climbing at high speed , cruising at high speed and descending at high speed use more fuel,(particularly in V/S)than they make up in time saved.According to my observations that is.

It does increase your chance of missing someone in a Fecked up situation, either an errant intruder or an unsure vistor to cas. If its good for that reason in uncas then its good for cas. Cant see any advantage to speeding up.

James T. Kirk
17th Jan 2006, 12:20
One thing that occurs to me is that pretty much every one can do the 280kts min clean speed of the heavy -400 but the -400s can't do the 250 standard speed without dragging flaps around and vastly increasing the fuel burn. My airline, a 737 operator wants us to get to econ climb speed as soon as possible after clean up for cumulative fuel (and emissions) savings. 280kts is a pretty good econ speed for the 737 and I should imagine most aircraft of that weight. Why not introduce a standard speed of 280 kts which every departing aircraft could adhere to and reduce fuel burn, flight times and emissions?

Kirk outů

17th Jan 2006, 12:31
As far as bunching goes, surely that is best avoided by everyone flying the same speed. What that speed should be will vary between aircraft types and operators requirements. Maybe the operators should be canvassed and then a compromise speed be arrived at. 280kts gets my vote, its a middle of the road speed with room to slow down or speed up comfortably by most types and closer to econ climb speeds than 250kts is. BTW this is the first i've heard of it as well.

17th Jan 2006, 12:32
OK, I realise that the point being made here is:What galls us is the fact that our tactical tools are slowly being eroded by management and based on the original question:What are your thoughts on this restriction?then as far as I'm concerned it makes very little difference except that anything that gets us pointed in the right direction and above all the low level traffic and on our way can't be bad. However, I am concerned if it is likely to be a retrograde step for you as an ATCO and is only being implemented as some sort of empire building exercise for managements pleasure.

Just done a check of my company's crew notices and not seen any info about this 'trial'. So, not filtered down to the coalface yet, but then again, we don't go above 250kts/min clean unless cleared to do so. Don't usually bother asking for it as I don't have the 'big BIG picture' anyway and the service provided is always top notch. Now, don't get me started about going into Boston! :yuk:

17th Jan 2006, 12:42
on the 737 the min clean is around 210-220 kts.Selecting VNAV will set the commanded speed at 250 kts.The speed restriction of 250kts/FL100 is set in the FMC ,and it's our SOP to follow that if not otherwise requested by the ATC.This will give the highest ROC to FL 100 ,most of the time.
The climb speed will be 280 kts( if turbulence expected) or something around 300 kts .
In London TMA,having to stop at FL60, we'll have to mantain 250 kts for a longer period of time.From what I've got from you,ATCO people,a higher speed will help by getting us faster out of your TMA. Of course ,with this trials that you've talked about ,things must be diff.
And,no,no-one told us at our comp about those trials you're doing at London TMA.

17th Jan 2006, 13:59
It's undoubtedly true that those on the various flight decks have no knowledge of this "trial". It seems to take a LONG time for the info to get from NATS to the Airlines to the Ops dept to the Pilots.

Why so? Dunno, but would hazard a guess there is a bottleneck somewhere on the airlines side. The info certainly is sent out to them.

The idea here is soley about better traffic presentation for aircraft exiting the LTMA, which will allow a greater throughput to the en-route sectors. The aircraft may not be at their best speed or even altitude, but they will be moving in an orderly fashion in the right direction.

The alternative is more departure restrictions, be they MDIs or simply holding selected traffic on the ground. Not good for anyone.

Whether a 250kt for all restriction is a good idea remains an untested one.

Bunching remains one of the biggest causal factors of Overloads. In the not too distant future the en-route sectors WILL refuse to accept traffic from the LTMA if poor presentation is leading to bunching and an unsafe situation. Just the same as TC quite rightly stop inbound traffic if neccessary.
Start to look at holding deps at SAM, DVR, CPT etc and stopping any futher departures until AREA can accept the traffic

With regard to LTMA inbounds, yes sometimes presentation is less than ideal and I regret that, and apologise. The reason is the short distance and high flight levels of traffic from Northern France. It's not always possible to restrict A/c speeds drastically in descent because they will not achieve the target levels. If presenation isn't brilliant, you can still "go vertical" and descend in the hold. Not pretty or pefect, but completely acceptable to approach.

There is no suggestion of "bashing" the opposition, be they AC or TC. The idea is to get the greatest (and safest) traffic through put. Examining long held cultures and ideas isn't always popular, but can lead to positive changes. There may be a better way.

Best rgds BEX

bad bear
17th Jan 2006, 15:43
I had not heard about the trial, but March is a long way away and I would probably have forgotten about it by then if I was told now.
250 below 10,000' is a good idea in my view. I am amazed how often an airprox is preceded by the words " no ATC speed restriction".
Maintaining 250 Kts will not only give better spacing, it will reduce noise, get us above the 4,000' noise restriction sooner there bye allowing us to leave the SID on a heading for a shorter routing particularly on LHR northbounds.
Will this mean we can reduce the departure interval on the Detling/Dover LHR departures?
So , yes this one gets my vote.

17th Jan 2006, 17:11
Bad Bear,

in short no!!

If it was a case of only having A/C coming from one airfield, or even from both heathrow and gatwick, then it would have a good chance of working, as for the routes it will affect, they are roughly the same geographical starting point.

Unfortunately it is not just those airports, it is a case of integrating traffic from London City, Luton, Stansted, and Northolt as well, plus the other low lying airfields in that area that kick out the odd flight now and again.

Tied in with needing to use vectors to get A/C away from lots of different inbound routes and the holds to enable a climb, the bunching issue will still be there.

If we do not vector off the SIDs (which would go a long way to preventing bunching)

a) Heathrow and Gatwick SIDS are not separated via DET/DVR
b) A/C would get much later climbs due to A/C now coming into conflict with others that would never have been a problem before....
C) The ATCOS job becomes much more difficult because there will be lots of A/C 8 miles East of Biggin needing a climb
d) all of the above would make things less safe

Just to clarify Bad Bear, it is the taking you off the SIDS to give you a climb that is one of the main reasons for bunching, as you are vectored out of any natural stream that may have occurred. Whether you are flying at 250kts or not does not change that fact!!

The only real way to prevent bunching is for all the London TMA airfield to coordinate departures with each other..... I am not going to hold my breath as that is totally impracticable

17th Jan 2006, 17:40
Nothing in the NOTAMS so far, when will this become effective????

17th Jan 2006, 17:53
Allegedley March, tho we have not been informed officially yet, the paperwork has been drafted, but not released.

We need 21 days notice, so expecting it soon; we have been told by management that the airlines have all been informed

17th Jan 2006, 18:04
we have been told by management that the airlines have all been informed

Ha, Ha! - rubbish:}

17th Jan 2006, 18:13
Well its not rubbish from our end. Our top guys have heard something, but nothing as yet to the troops.

17th Jan 2006, 18:14
It may well be that all UK airlines HAVE been informed, but as someone said above, they may not have distributed it a month or so early?

17th Jan 2006, 18:37
Well it'll stop our 14sicks holding up everyone else

17th Jan 2006, 19:35
Possibly a few urban myths here.....If we do not vector off the SIDs (which would go a long way to preventing bunching)

Actually, vectoring off the SIDs has been the CAUSE of much bunching.
There is a "culture" issue here.
As ATCOs (everywhere) we spend our time trying to shorten routes, climb a/c asap etc. Often we are our own worst enemy in that by shorting routes, and not stopping off climbs, we create many more conflicts than would actually exist if everything WAS left on the SIDs and climbed to vertically separated levels.
I might also take issue with:a) Heathrow and Gatwick SIDS are not separated via DET/DVR True. But if you stick to VERTICAL separation they can be. The two tracks do not merge until DVR. Ample time for some parallel headings or even a little dog leg to position one behind the other. Positioning is more important than an early climb.
b) A/C would get much later climbs due to A/C now coming into conflict with others that would never have been a problem before....
So? if capacity is increased, being "held down" for 7 mins or so (28 miles) seems a small price (particularly when the overall journey is one of Several HOURS
The ATCOS job becomes much more difficult because there will be lots of A/C 8 miles East of Biggin needing a climb
There's that culture thing again, "Needing a Climb". Sure, they will need to be climbed, but it's NOT that urgent. Better positioning (and capacity) is what we're after here.
d) all of the above would make things less safe
. Disagree here. Safest form of separation is VERTICAL, it's also the quickest and easiest to apply.

Next time you have the opportunity in the SIM, try it. Keep the sectors split so you have plenty of RT time Leave the a/c on the SIDs, restrict climb to vertically safe levels, and have a go at positioning the a/c in trail later in the SID. All the target levels to AREA are climbing to, rather than level at, so there's no rush.

It IS a BIG culture change, and many people don't react well to change as we are all too well aware. But try it. I have. It DOES actually work.

Best rgds

Charles Darwin
17th Jan 2006, 20:42
I very much appreciate the higher speed (at 6000┤)to get out of London TMA. No reason though to blast through the first turns at high speed, but when on a straight course the higher speed is very much desired, weather permitting og course.
p.s. In the U.S (the land of the free) ATC is not at liberty to cancel the speed restriction. It┤s the law!;)

18th Jan 2006, 04:54
Here in the States we do, indeed, adhere to a 250 kt below 10000' restriction. Houston TRACON (Dep/Arr controllers) did have a waiver to eliminate that restriction for a couple of years as a trial but they have since rescinded that and have restored the 250kt restriction.

Standard reason for having the speed held to 250kt is because of all the uncontrolled (i.e. general aviation) traffic below 10000'. I would think that even though there are not the numbers of light aircraft in the UK that there are here you still have a significant number clustered around your terminal areas and you would want to get the jets up and out of your lower airspace.

My company's SOPs require us to climb at BESEC (green dot for the 'bus) to 3000' agl before we accelerate to 250kts. Certain departure procedures like ATL and LAX want 250kts right away so we give them that.

Hopefully I will be flying into the UK in the next year or two after we sort out this merger so I will look forward to working with you gents in ATC. Until then I will keep myself up to speed as best I can via these discussions.

18th Jan 2006, 10:36
Another half-baked bonus-related management initiative - deep joy.
How can this increase capacity when the outbounds will be on the TC freq for a considerably longer time? Thereby reducing RT capacity - one of the great criticisms from aircrew these days is not being able to get in on the RT.
Miss the stack, climb like the clappers and give them to AC - then take on the next wave.
My very first "airmiss" 25+ years ago was a 727 departing given " no speed "
rapidly rammed up the rear by a " restricted" DC-9 on a different SID (& freq).
The sectors ARE split as often as possible and, in any event, only takes a few seconds to achieve.

18th Jan 2006, 16:02
I must disagree with the comments regarding bunching of aircraft out of the TMA. One of the main reasons for bunching must be the large tollerances to slot times airfields are given. DVR's from LL always meet DVR's from KK!
I see restricting aircraft to 250kts, increasing my work load and increasing noise to the environment because not all aircraft will be able to clean up.
I want high speed, if possible. so I can get aircraft up and away to another frequency.
I do not see this trial lasting long or being fully adhered too.

18th Jan 2006, 16:09
We were informed a couple of days ago about the trial in march.

18th Jan 2006, 16:41
Is this going to be similar to the trial currently being run at Manchester or is the said trial at Man now a fixture and fitting?

19th Jan 2006, 14:34
According to the airfield plates, it's now a fixture and fitting..
Although if it's quiet, the restriction is cancelled.


19th Jan 2006, 16:25
Danny -- on many occasions I have gotten "fly your best operational speed" directive from controllers out of some the U.S.'s major airports, including my last flight 2 days ago, on a aircraft that not to often has a clean speed over 250. So I'm not so sure on your comment that it's standard SOP not to be given over 250kts on departure. From what I understand the 250 rule under 10k is intended primarily to guard fast aircraft from effects of bird strikes. A valid though operationally frustrating concern since the most economic dep is always best rate climb from the ground up, correct?

BEXIL160 -- Vertical seperation safer than lateral seperation? how so?, I know that in LAX our company consulted with ATC as to if they reallly need the 250kt directed sid speed on our usual dep, and were told absolutely since there key concern was not vertical seperation (we could have flown the VNAP A procedure) but lateral seperation, because heavy's and lighter jets use the same or parallel runways for dep and the need for wake seperation. Another example is at YYZ in Canada where lateral seperation also seems more important to ATC as even on the ATIS you are to advise if you will intend a less speedy but more vertically efficient noise abatement procedure.

19th Jan 2006, 17:49
I don't doubt procedures my colleagues use in the US or Canada. Bigger places, more runways, different ATC "culture" etc, and the guys there do a great job.

Vertical separation in the UK? Because its quicker to apply (Think TCAS). The conflicting SIDs from EGLL and EGKK, aren't laterally separated (by enough). They ARE vertically separated by ATC, at least initially.

Using this inbuilt vertical sepn, and some tactical vectoring aided by the 250kt limit, it may be possible to increase the movement rates for departures. Deps would all become a lot more "systemised", and a lot less "point and shoot".

Downside? Less early climbs (not above 6000ft or so for about 7-10 mins), but more unrestricted climbs once with AREA.

To reiterate, the idea is an attempt to up the departure rates and still keep things orderly (and safe). It is a big culture change for some in UK ATC, and hence the percieved difficulties. Just because somethings have always been handled a certain way or ways, it doesn't mean that you shouldn't look for other methods that may improve traffic through put.

Keep an open mind. It's a trial at moment.

Rgds BEX

19th Jan 2006, 18:08
A question for our US airspace experts (if I may):
FAR91.117 Aircraft Speed states in para(a) 'Unless authorized by the Administrator, no person may operate an aircraft below 10,000 feet MSL at an indicated airspeed of more than 250 knots (288 m. p. h.).'
Para (d) states 'If the minimum safe airspeed for any particular operation is greater than the maximum speed prescribed in this section, the aircraft may be operated at that minimum speed.'
As others have already stated many of the 'heavies' at high weights will have a min clean above 250kt. Can therefore para (d) be applied - are min safe & min clean synonymous in this context - or should I be climbing with Flap 1 to 10,000ft?

19th Jan 2006, 21:30
Didn't have a clue but my company only tell us about fodcoms six months late and are implementing cap371v4 the day before they have to!!!:}

20th Jan 2006, 03:14
A question for our US airspace experts (if I may):
FAR91.117 Aircraft Speed states in para(a) 'Unless authorized by the Administrator, no person may operate an aircraft below 10,000 feet MSL at an indicated airspeed of more than 250 knots (288 m. p. h.).'
Para (d) states 'If the minimum safe airspeed for any particular operation is greater than the maximum speed prescribed in this section, the aircraft may be operated at that minimum speed.'
As others have already stated many of the 'heavies' at high weights will have a min clean above 250kt. Can therefore para (d) be applied - are min safe & min clean synonymous in this context - or should I be climbing with Flap 1 to 10,000ft?

It's generally understood to mean "min clean speed." Clean up, fly fast, and just mention to ATC that you WILL be climbing at 280/300 or whatever.

20th Jan 2006, 11:24
When going north from lgw, all I want to know is how high you want me to get over the stacks at BIG, 220kts to 8 or 10k with 6000 a min + can save 10 mins if I can go straight over LHR towards TNT, instead of going round to the dartford crossing.

20th Jan 2006, 11:52

How long is a piece of string??

How high depends on what is holding at BIG at the time.

You NEED to be FL130 by the time you cross the EGLL centreline.... theres a nice gap at that level in the Lambourne stack if the next sector can't give you higher.

Depending how you climb will determine when you get turned... If you are just on a jaunt to EGPH or similar, you will climb well and therefore if not holding high at BIG, you should get a fairly early turn.

If you are off to the States and are heavy, on a hot day, with BIG holding up to FL150, we will get higher from the next sector and climb you to that..... the problem then is turning you tight enough or getting you high enough to miss traffic coming to Lambourne from the east.

If there is nothing at OCK and you are climbing well, you may even be given vectors to the NNW initially to keep you away from BIG traffic.

Most controllers will keep your speed restriction on for the LAM departure from lgw, this helps us and you.

The reason this thread started was that myself and colleagues at TC are unhappy that using speed as a tool is going to be taken away from us. It does not affect the LAM departure as it is a handover from one TC controller to another; it is AC that want us to trial the 'keep everything slow'

Cartman's Twin
20th Jan 2006, 15:03
BEXIL, I just have to ask, how long has it been since you've plugged in on a TC sector and seen + heard the sector working?

I'm a South TC ATCO and visit your den every couple of months. I think there's a great deal to be learned from it. Maybe management should encourage it more...

If a/c aren't climbed and transferred ASAP overloads will become the norm. There are enough a/c on the BIG sector freq as it is without doubling the number of planes at altitudes. (And yes in this example the sector is already split!)

Returning more to the subject of our colleagues post this will do so little to ease bunching. So long as heavys can increase to min clean speed I don't see it doing too much harm either.

20th Jan 2006, 15:06

How dare you.... Bexil has tried it in the SIM and it works!!!

20th Jan 2006, 15:42
Questions, questions...

Cartman: Two months ago. I agree lots more liason visits required both ways. Better still, when TC are re-united with AC, dual Validations (now there's an idea....) ;)

535 : Correct. The sim is not reality. That's why there is to be a trial.
it is AC that want us to trial the 'keep everything slow'. No, AC would like more orderly presentation in order to increase capacity. The speed trial is a TC Ops initiative. 250kts only applies at or below FL100, so not an AREA issue at all.

Open skies, closed minds? Try it (with out bias) and see. Go on, I dare you .

You (or I!) can't "know" if it doesn't or does work by any other method.

rgds BEX

20th Jan 2006, 18:52

Thanks for the reply. Any more views out there on this?
The reason for asking on this bulletin is that 'the trial' to be conducted seems to me to be much on the lines of FAR91.117: 250kt below 100 rigidly enforced with no controller discretion to cancel. There is a bit of an irony here in that if a heavy is not allowed to accelerate to min clean, he may be flying at a speed a lot less than 250: a 763 Flap 1 placard speed is 250kt, so if I'm wizzing around with flap out, don't expect me to be doing more than 240.

Don't know the position with other types, but presume the bigger Boeings & Airbuses are similarly affected.

20th Jan 2006, 23:09
Sounds like tunnels in the sky to me!!!!!! :D



21st Jan 2006, 11:05
Merely a pilots input here, so I don't have the vast airspace depth of knowledge of the TC/AC controllers regarding daily issues created by this.

Personally I can't really see how 'bunching' will improve purely by limiting LTMA departures to 250kt. I fully accept that 'bunching' is a major issue - and always has been. I'm just not really sure that this is the answer to it. Slot tolerance across all departures is far more critical, as is mix of traffic from ALL uk airfields to an exit fix. A take-off just one or two minutes creates, or cures the problem on many occasions. This of course can never be calculated, predicted, with mix of traffic from various points all under different variables.

Can someone confirm also that this applies ONLY to LL/KK/GW/SS departures. I presume BB depatures for example into COWLY/WELIN are uneffected by this trial??


21st Jan 2006, 16:12
The official paperwork is still to come out, but I believe it is from TC TMA airfields only, and i agree with you - the only way to stop bunching effectively is to have departures from airfields co-ordinated - which would impinge far too much on carrier operations

21st Jan 2006, 19:25
Just curious, but what would be the min clean speed for a heavy A340?

(I'm postulating about the one posters idea of bumping 250 to 280 below 10K.. and its effect on other planes... not sure how the 340 would fare with that, while trying to maintain a reasonable ROC)

21st Jan 2006, 19:52
Hi All,
I know 'information is power' but here are typical speed ranges for the -300 and -500. I have no info on the -600.
A340-300 at MTOW is 280kts whilst at 40 tonnes less it's 256kts. For A340-500 it's 269kts and 253kts respectively.
REF QRH 4.01. (Please allow for rough interpolation :hmm: )
Hope this helps,
Happy Flying

21st Jan 2006, 19:54
An A343 at 250T or an A346 at 360T will have a green dot (min clean) speed of around 265.

Turn It Off
21st Jan 2006, 23:54
Make all airspace above FL105 Class A or B.
Make More Airways.

Easy!!!!! :ugh:

Jambo Buana
22nd Jan 2006, 16:46
No Flight Crew Instructions at Ryanair yet for your info.

I am interested to know whether the EGCC constant IAS departures/arrivals helped ATC at all and is this idea goin to be expanded on at all?

On another note could this speed control be a good pre-emptive strike by your management in an effort to slow us down for the arrival of PRNAV RNP 1 operations? I suppose PRNAV SIDs and STARs will help reduce your workload whilst improving our efficiency too (ideal world stuff, I know). But to stay on PRNAV routes may well require this kind of speed control, I would imagine?

Is there a culture in ATC (from reading between the lines) of controllers who prefer to "control with the autopilot engaged" and those who "control manually" i.e. remove the protection of some of the system to help us out kind of thing? Surely it must be easier for you to leave us on the SID provided there is no conflict at the point you hand us of to Area?

22nd Jan 2006, 17:04

"which would impinge far too much on carrier operations"

In my experience the effect on runway capacity rates by doing as we suggest would have airfield operators, BAA etc up in arms far before the carriers even realised what was going on :O I think in this modern game of politics they have far more weight at consultation than operators ever do :(


I don't think you'll find the PRNAV SID's looking very different from current ones. There is VERY limited space within the LTMA and capacity, like my note above is heavily monitored. The UK, through DAP, have developed their own PRNAV SID design criteria. If the ICAO one had been followed, then there would have resulted in many problems within the LTMA. For instance, speed on first turns has been 'capped' on UK design, specifically to cope with the LL/KK SID problems already discussed by controllers.

Also the UK set it's own higher Procedure Design Gradient (PDG). Much effort and careful analysis went into setting the UK figures - with pilot input I add. This new TC rule however would NOT be because of this new PDG.


22nd Jan 2006, 18:48
Friday 20th midmorning Brookmans park departure of 27R:

"maintain 6000, no speed restrictions"

Is there a trial or not. Mind you, we had to fly the whole sid and stayed at 6000 for a very long time.

22nd Jan 2006, 19:13
The trial starts in March - as stated in previous posts

Bomber Harris
23rd Jan 2006, 11:38
Wow, you flew a SID. I have have a vague memory of completing the clacton out of STN a few years ago, but the altitudes and speeds where lifted, so I guess I can't really say I did it!! In fact the last SID I can really remember flying was my instrument IR.

Dublin has 12 pages of FMS STARS. Thats more that ATL or DFW I bet, and DUB is just a pissy little airport compared to some big US fields.

There really is a big descrepance between the disney jepps and ATC needs. Can we not rename SIDs and STARS as 'radio failure procedures' and just make all clearances 'rwy hdg to 3000 feet and expect radar vectors to ####' (first point on a/way).

Jeppessen are supplying us a disney book for a lot of money. Half of it (SIDS and STARS) is not used!!

How have things ever become like this? (ooops hijacking the topic). Maybe i could rephrase the question; how did we get to the point that we are implementing a "trial" for something that already exists in the rules!!!!!????

23rd Jan 2006, 13:44
Bomber makes a good point; we almost never fly either SIDS or STARS at LHR or LGW. What we really have on arrival is a number of holding fixes to which we are vectored, and on departure we follow an initial procedure to maybe 3000' and are then vectored to a downroute fix. Speeds in either case are often directed by ATC. So why do we bother pubishing a few forests' worth of SIDS and STARS we're not going to use?

Better to publish a single departure plate showing initial climb procedures and listing frequencies for the various sector departures, and a single arrival plate for each hold listing the speed restriction distances from the hold (or, radically, emphasising the 250 below 10 restriction!).

I have no idea whether the forthcoming trial will make any difference to ATC, but it seems unlikely to make a difference to us!

23rd Jan 2006, 14:51
In most cases the initial SID route is totally dependent on noise preferential routes. At LHR once above 4000ft you can be taken off the SID; trouble is, the point at which you in your shiny A320/737 reaches 4000ft and where the Virgin 340 going to LAX reaches 4000ft are quite far apart:D

23rd Jan 2006, 15:00
Hmmm. Mine is the VS340! However, I know what you're getting at. That said, if the only common portion is the noise preferential route to 4000ft, what's the point of publishing anything beyond that?

3rd Mar 2006, 14:54
The following was posted on a forum of the flight crew website on 02nd Mar by our ATC Liaison Pilot:
London Terminal Control will commence a speed limit trial affecting all departures from London TMA airfields from 8th April. Simply stated: your speed will be limited to 250Kts or min clean speed, whichever is higher, until passing FL100.
All that you will notice is that ATCOs will not issue the instruction "no ATC speed restriction" on departure other than (exceptionally) for tactical reasons.
Still waiting for 'official' notification from The Management.

3rd Mar 2006, 15:50
The 'tactical reasons' is nice

That means that I will be taking speeds off as and when I want and usually well before the FL100 mark. After all, I am the one who is using my license, and I will dictate my tactics on how to run my sector, not some non controlling management person.

Not Long Now
3rd Mar 2006, 16:40
I believe the 'official notification' is pinned to the wall in the briefing room above the two PC's.
As for the 'I'm doing it tactically, all the time', I'm led to believe that will be a matter between you and your LCE.

3rd Mar 2006, 19:06
I may have missed the point, but I think nothing has changed. The charts we use state that departing LHR we are limited to 250 kts until reachimg FL100. Up to now, at the discretipon of the controller, we have been allowed to accelerate beyond that restriction below FL100. From March, they will no longer be able to offer any deviation from the speed constraint. So technically nothing has changed and therefore there is nothing to inform the crews about, although it kwould be nice to know if only so you know not to even ask for high speed.

4th Mar 2006, 10:32
Just had a look at the last 3 months of information that our company churn out and i can not find any mention of this trial going ahead in March, but iam not supprised. TCX

4th Mar 2006, 14:28
Based Manchester, UK - they have "speed profiling" on southerly SID's with 250kts to FL100 then 280-290kts to FL260
Manchester area then hand you off to London who want you up at FL310 50 before Midhurst - try doing that in a heavy A321!!
They then promptly cancel the Manchester speed restriction because they want you out of the way and would rather you make as high as you can get, regardless of speed, which makes a mockery of the speed profille in the first place.

4th Mar 2006, 15:11
Based Manchester, UK - they have "speed profiling" on southerly SID's with 250kts to FL100 then 280-290kts to FL260
Manchester area then hand you off to London who want you up at FL310 50 before Midhurst - try doing that in a heavy A321!!
They then promptly cancel the Manchester speed restriction because they want you out of the way and would rather you make as high as you can get, regardless of speed, which makes a mockery of the speed profille in the first place.

These ideas are not made up for the fun of it. As I understand it, there was a lengthy discussion process with all the airlines involved in this speed trial, and they all said it would not affect their ability to make existing level restrictions. If you are finding that this is regularly not the case, then you should be feeding that back to your Flight Ops to progress with NATS Ops.

5th Mar 2006, 08:58

the 250kts on departure from Manchester are to prevent bunching of aircraft - it works in this case because it is a single airfield.

Whether the 250kts in the London TMA will prevent bunching from several different airports remains to be seen.

If you feel there is a safety implication with the Manchester procedure (and tha would include making you feel under pressure) then you should report it.

one four sick
5th Mar 2006, 09:29
Most of the time the response from ATC on first contact inbound or outbound is No Speed! Now the company's silly rule is the overriding thing so it is 250/100 anytime anyway! Annoying or what?

5th Mar 2006, 10:08
Thanks UKATCO - already reported it via the NATS website link

250 kts
5th Mar 2006, 18:21
I'm not sure whether it matters if the speed is 250kts(:ok: ) or,say, 280kts. The crucial thing is that the traffic is presented in the same manner in order to reduce bunching at the interfaces,be it to the next sector or unit. I recently watched an incident between 2 a/c on the same SID from the same airport,100 miles north of the departure field,similar types-and no,not an A340 involved, and they had an airmiss. Now if they had been flying the SID and a similar speed there is no way that the in-built airfield separation could have been eroded so much.

It seems that the airlines want a "pile'em high,sell 'em cheap" type of service nowadays and are interested purely in sector throughput and eradication of delays. This will require a major re-education amongst the ATC fraternity and will not be a painless experience. From an en-route point of view it is the bunching which causes the major problems so this has to be worth a try for at least a couple of months and people not giving it a fair chance will not help the validation of such a procedure.

5th Mar 2006, 18:34
250 is not a problem, for A340 ,but why not just use 280 below FL100 and everyone will be happy

250 kts
5th Mar 2006, 19:56
ipAQ. The Manchester streaming trial has reduced delays considerably on the airfield at Manchester. It was a regular occurrence for a Minimum Departure Interval to be put on the departures to the south,often at short notice. This led to airfield delays often without notice. This trial has meant that the traffic is presented to Daventry sector in a known and expected manner leading to the lack of need for last minute restrictions and therefore a more regular and consistent service to the operators.