Height Capping

[fuzileer]

What exactly is height capping? Denial of particular altitudes for ATC's convenience?
Some people I've been talking to imply that there's been more of it going on in UK airspace since Swanwick went live, but airlines don't seem to be complaining from what I can see.

Any thoughts????

[Arkady]

Height capping is a form of flow control becoming more popular as the number of vertically split sectors increase across Europe.

Climbing aircraft will be "kept down" so the higher sectors can take a greater number of overflights. In a sense inbound flights are also capped, by forcing them down earlier than they would like, giving a predictable profile for flow management purposes.

Airlines don't seem to mind as level capping is better than delay.

[Scott Voigt]

Fuzileer;

You've already heard what the capping is... As to the airlines, they are the ones who asked to do it here. When asked what they could do to get off and not take a delay due to congestion, they were advised that in some areas they could take them FL230 and below... They much prefer this to staying on the ground or getting miles in trail through an effected sector. We did some of that today at work. It caused some flights to go about 300 miles or so at the lower altitudes before they could get up to more efficient altitudes...


regards

Scott

[fuzileer]

Many Thanks for these replies...



Fuzzy....

[Lon More]

often used by Maastricht on departures from London TMA requesting FLs 350 and above basicly to reduce the amount of co-ordination LACC has to do with us as 90% or more of the traffic is below 330 when entering our airspace. Furthermore as traffic in the middle sector is normally lower at that time it gives us more possibilities to solve conflicts in the SPY/PAM area.Climb above FL330 is normally given within 3 - 4 minutes or at the latest just after he coast.
Airlines prefer it as the alternative would be restrictions.

Lon More,
More than just an ATCO

[250 kts]

Lon,

I always thought the reason for the 330 cap was because the high level sector was too busy. Most people don't put traffic ex SS above 330 just so they don't have to co-ordinate but there are many departures ex LL/KK that could make 340+ and so no phone call necessary. Often that would aid things at our end-after all if they are parallel at the lower levels we still have to make a call so not saving anything on your part.

Just tell us no co-ordinations allowed from lower into upper rather than a level cap and we'll sort it.

[Lon More]

250 - Sorry I was not very clear, and before TT jumps in, it does reduce the traffic in the Upper Sector. We do it when the Upper Sector TACT indicates an overload in the Upper Sector whilst the middle sector is relatively quiet. It also has a benefit in that we can sort the traffic out onto the correct sides much quicker, also if you are climbing higher the traffic is still coming much too late, often 20nm after the boundary, onto the freq., still on what, by that time, are irrelevant headingsas vertical separation has ben achieved. When busy this is a major irrritant as the worry lurks that there is someone we've overlooked.

Lon

[250 kts]

Lon,

Thanks for that but I have to say in my experience traffic is transferred late usually as a result of the sector being busy elsewhere(after all we are only human and do occasionally make mistakes and don't forget that S12 cannot be split), but not to the extent you say. A phone call is usually initiated by Maastricht within 10 miles of the boundary if not transferred. It is unfortunate that we have the cross against the traffic from the North Sea so close to the boundary but that's just part of the game I guess.

[DC10RealMan]

I was chatting recently to an Airbus Captain about this. I was told that LHR-Glasgow by flying at FL260 and not FL 360 the aeroplane burning about an additional 200 kgs which in fuel burn terms is nothing.

[Lon More]

250 , as you said we will normally call within ten miles - however before the initial call afurther 10/15 miles has often been covered Unfortunately this is a daily occurence.
That you are busy elsewhere is not of our concern, ( not being rude, just stating a fact) we have our problems too, one of the biggest one's being caused by having to swap traffic over ( I know, you get them that way from TC)
When it comes down to it, the TOC point is the boundary, with Coms. transfer before that.
If level capping means that we get the traffic in time, and we have seen that it helps, then we will carry on doing it.

(apologies for spelling and punctuation - new laptop withno spell checker and an Australian ? keyboard - every thig's upside down)

P.S. TT if you read this, you can have your own Boston Tea Party next week

Lon More

[Moondance]

DC10RealMan - 200kg may not seem particularly significant on a single sector, but imagine the cost of that on every GLA - LHR for a year!
How effective is height capping? I have been height capped many times, when operating outbound from UK Airspace. Typically the restriction is something significantly below FL300 until the UK boundary, but on EVERY occasion (apart from maybe a brief delay at the low, UK flight-planned level), the climb to near optimum FL has been almost continuous. So a big thanks to all of you who expedite our climbs through these "academic" restrictions.

[Scott Voigt]

Moon Dance;

The fuel burn is when you take into the account a delay if you were not to cap is not that bad. What happens to your costs if you have a lot of aircraft that are delayed going around the system and then you have crews going over duty time and then out of position for the next day??? You have to look at the entire picture to understand why you take a little bit of cost in one place to make up for a greater cost elsewhere.

Most airlines will do just about anything to get into the air and try to keep schedule...

regards

Scott

[TrafficTraffic]

I am worried you thought I would come in with some negative opinions LM on how your english brothers handle the traffic and the use of level capping.

I think you do a great job with the roster, London CLN does a great job with parallel headings and getting the traffic on the correct geographical sides. Mohammed Saeed al-Sahaf

oh yeah


Their failure in this regard is abysmal. They want to tell the world changes thought - as a matter of fact, they do not respect the world, they want to tell taxpayers and the domestic public to keep them deceived. We will embroil them, confuse them and keep them in the quagmire. They have begun to tell more lies so that they might continue with the perpetration of their crimes. May they be accursed. Mohammed Saeed al-Sahaf"


P.S. Never heard of a Laptop with an Austrian spell checker

[Lon More]

TT What you been drinking? Cant find the source for your quotes

BTW , not an Austrian spell checker, more a spell chucker , Jet Magic maybe?

[ZRH]

We make use of Level-capping every day. It affects primarily tfc outbound EDDF and EDDM with destinations in northen Italy for the Frankfurt departures and Lyon/Geneva for the Frankfurt and also Munich departures.
These flights are then restricted to F230 in the one direction and F220/F240 in the other direction.
This measure of flow control was introduced to relieve the upper sector which works tfc between F250 an F300.
Funny thing though is that this sector used to run at or above capacity most of the time, and now it runs well below capacity.
Most of my fellow ATCs dont understand that the requested flight level in the flight plan is not really "the requested" flight level, but the level-capping flight level. And when you phone the next sector and tell the controller that there are no restrictions for one or more tfc which you have observed cruising along well below your sector, he aks the pilot "what is your requested cruising level?" The pilot answers politely "F230" as he filled it out because apparently the ATC providers have complained to the airlines about asking for higher levels when they dont have a slot in the upper airspace.
I tell my colleagues that you should phrase the question correctly so that the pilot understands that your offering climb and not just checking details on the flight plan.
In my mind, level-capping is very restrictive and in our airspace it "punishes" our biggest customer ie. Lufthansa. But the folks here reason that the pilots should always fly at their "requested" flight levels and not be given climb to higher, more economic flight levels.
Providing a service when you have the capacity to do so is a non-entity.