UK Stacking Areas

[Shaz SBFS]

Does anyone know which is the biggest/largest/busiest stacking area in the UK.

I live under what is called the Bovingdon Stack and this is quite busy. (to an untrained member of public :O )

This morning's skies were very clear and I watched a number of planes stacking and the above question popped into my head. I have trawled the internet to find the answer, but cant.

Thanks in advance

[HEATHROW DIRECTOR]

Probably any of the Heathrow holds - Bovingdon, Lambourne, Biggin or Ockham - will be very busy at times.... but so will plenty of other holding areas. I doubt very much if it would be possible to state categorically that one holding area was the busiest because only a certain number of aircraft can be accommodated so you will never get one holding area with a vast number of aircraft holding..

Hope that makes sense!

[Shaz SBFS]

I should have thought of that !! :O

You can only get a certain number of planes in a place at the same time!

At least there is Bovingdon Airfield if you need to make an emergency landing.... ;)

(if you dont mind the bumps and holes in the runway :eek: )

Best wishes

[HEATHROW DIRECTOR]

Theoretically you might be able to get 20 or more aircraft holding over one point - they are separated by 1000 ft vertically. However, the amount of space available in the vertical plane may be limited by traffic overflying or other constraints. Similarly, the horizontal dimension of the holding area is clearly defined so that aircraft holding do not conflict with aircraft passing close by, or holding in adjacent holding areas (but this does not necessarily limit the number which can be held). During very busy periods, perhaps during low visibility operations, the "inner" holdings stacks (of which Bovingdon is one) will take a certain number of aircraft (my aged brain won't remember the limit) and subsequent aircraft are held further out at much higher levels..

It's all clever stuff!

All the best...

[5milesbaby]

To add to HD's point of holding out, when the loading for any one of the inner stacks is excessively high then a/c can be 'stack swapped' to another of the inner stacks and held there instead. I would say that Lambourne is one of the busiest however Ockham sees alot of traffic too. The usage of the stacks can also vary between each day due to the routings into the TMA altering due to en-route winds and weather. For instance Bovingdon will get very busy if the North Atlantic tracks are far north, but then the next day Ockham could be busier with a more southerly flow. As LHR plans to have a good 20 minutes of traffic holding at any one time then I'd expect the answer to your question to be one of their four.

[Shaz SBFS]

Wow...that just blew my mind!! :confused:

A bit technical for the likes of me!!! :D

TMA, LHR ..inner stacks ??? I'm lost there!

I only watch all the planes going around in circles :O

Best wishes

[WHBM]

Although we live close to London City our kitchen and back garden are visual with the LAM holding traffic, so I get a good idea in good vis of how things are going when I am doing the washing up !

One thing noticed during the BA strike last August was absolutely no holding at all !

When inbound from the North East, which as pax I am quite often, the first sign of trouble is if you are held overhead the Clacton VOR. This seems to be done when LAM is getting up to capacity, and has always in my experience been an indication that you will get a LAM hold as well, so the question of which could be the busiest is a bit complex as part of the load is held further out.

Lambourne VOR is on Stapleford airfield (home of G-WHBM) and in good weather out there it's always interesting to note the quantity of traffic holding.

[5milesbaby]

Sorry Shaz, didn't wish to lose or confuse!

TMA (Terminal Monouvring Area) is the area surrounding the London Airports of which Heathrow (LHR) is obviously one. Its basically a big mass of airspace where all the inbounds and outbounds from the London Airfields can be kept safe and adequately separated. Its upper limit is about 17,000 feet. the four main stacks for Heathrow are known as the inner stacks, but when these get full we start holding aircraft further out, for instance as WHBM out by Clacton VOR at a point called BRASO. All the surrounding ATC sectors have holding points for many of their routings just in case they cannot get into the TMA.

Hope that helps and explains a bit better

5mb :ok:

[Shaz SBFS]

Thanks for that..I do understand a bit better now, but it also leads to another question.

If the inner stacks are full and there are holding areas outside of this, would these areas, in the case of Bovingdon etc.. affect say.. Luton stacking area and/or any other airport by overlapping?

I suppose what I am asking here is, how does an airport (Heathrow in this case) accommodate heavy traffic? I assume they must have 'free slots' of some sort to clear a backlog!

Best wishes
Shaz

[WHBM]

5milesbaby:

Thanks for the professional clarification, always assumed we were actually doing a VOR hold out at Clacton, seems we are not !

[GOLF-INDIA BRAVO]

The 3 holds for Manchester are Dayne (Southern arrivals),Rosun ( North and East) and Mersi ( West) which can get quite busy at times though not as busy as Heathrows


G-I-B

[5milesbaby]

No, all stacks have a protected zone between certain level bands and those aircraft that have to hold further out also hold at higher levels so no infringement occurs. Also, if a level is being used that is unusual for the stack then we have written down which of the other stacks are infringed and therefore the particular level cannot be used there.

For instance, the upper level at Biggin for general use is FL150 as FL160 and above cannot assure separation from Lambourne, so Lambourne uses FL160/FL170 and Biggin doesn't. Or something like that anyway, I'm sure HD or another LHR controller can give the specifics better!