Holding patterns: UK vs US
Thread Starter
Joined: Apr 2007
Posts: 153
Likes: 287
From: Hawaii Island
Holding patterns: UK vs US
This is simply a query about possible differences between arriving at busy airports in the UK versus those in the US. I'm curious about one thing I've noticed over the years and hope someone with experience of flying between the UK and US might be able to explain.
Typically, when flying from the USA to the UK (Heathrow in most cases) the flight I'm on has to go into a holding pattern at some point short of London. The flight deck crew normally announce this and it's fairly obvious anyway, the window seat passengers (e.g., me) get to see the view a few times over, which I quite like!
On the other hand, when I fly from the UK to the USA, usually London to Chicago, I can't remember the last time I was in an obvious holding pattern near ORD. It's the same thing when I fly onwards to LAX or SFO, I cannot remember one time I was in an obvious hold yet these are busy airports.
Have I either been lucky or is there a different procedure in the US compared to the UK?
Typically, when flying from the USA to the UK (Heathrow in most cases) the flight I'm on has to go into a holding pattern at some point short of London. The flight deck crew normally announce this and it's fairly obvious anyway, the window seat passengers (e.g., me) get to see the view a few times over, which I quite like!
On the other hand, when I fly from the UK to the USA, usually London to Chicago, I can't remember the last time I was in an obvious holding pattern near ORD. It's the same thing when I fly onwards to LAX or SFO, I cannot remember one time I was in an obvious hold yet these are busy airports.
Have I either been lucky or is there a different procedure in the US compared to the UK?
Joined: Feb 2000
Aviation Qualifications: SLF
Posts: 2,222
Likes: 60
From: Anderlecht
ATC in the USA generally have a lot more airspace to play with, and don't forget that the major airports use multiple runways (anything up to six) simultaneously. LHR only has two; Gatwick, Luton and Stansted one.
Joined: Oct 2009
Posts: 290
Likes: 0
From: The Isle Dordt
In the USA there is (relatively) more local traffic when the Transatlantic flights arrive. Local flights will be held at their departure airport if they need space for international arrivals. OTOH, most of the early morning Heathrow arrivals are transatlantic and already in flight when London makes its arrival planning.
Joined: Feb 2002
Posts: 477
Likes: 0
From: East Midlands
If you ever fly United, you can usually listen to live ATC on channel 9 of the inflight entertainment, and this can lead to a better understanding of what ATC typically gets up to.
My experience from listening on Ch9 is that inbound from trans-Atlantic the hold to LHR will usually be at Bovingdon (or occasionally Ockham), and might be preceeded by some speed restrictions once the flight is well past Manchester. More likely though ATC doesn't ask for the speed to come back until past Birmingham once the flight is well into the decent.
Contrast this with an inbound [for example] to LAX from LHR. If the track is through the midwest, typically speed restrictions and minor course deviations will commence in the Las Vegas area and sometimes well before that whilst the flight is still working Salt Lake or even Denver center. If you start hearing non-weather related course and speed changes inbound to LAX whilst over somewhere like St.George, UT its usually a fairly safe bet that flow control into SoCal/LAX is at the root of it. The restrictions will continue and sometimes get progressively more all the way to LA. Same is often true with speed restrictions well away from gateways like ORD, SFO and IAD - into IAD I've frequently heard ATC instructing inbound speed restrictions and course deviations prior to or in the NYC area, and inbound to SFO whilst still well up over northern Oregon or well before overhead Reno (depending on inbound course).
As has also been said, the US seems to hold domestic traffic on the ground at point of origin when significant congestion at a hub is forecast.
Long and the short of it is that the US typically has much more airspace to play with and ATC sequences traffic using speed, course and altitude restrictions far far further out from destination than can ATC in the UK where if they started slowing traffic out over the Atlantic they'd get some "interesting" backups and also potentially impact traffic into non-flow limited airports. Of course, pax are far less likely to notice a speed restriction than they are going round the racetrack at BNN or OCK, and its easy for the airline to announce a hold and blame it on ATC in London...
Andy
My experience from listening on Ch9 is that inbound from trans-Atlantic the hold to LHR will usually be at Bovingdon (or occasionally Ockham), and might be preceeded by some speed restrictions once the flight is well past Manchester. More likely though ATC doesn't ask for the speed to come back until past Birmingham once the flight is well into the decent.
Contrast this with an inbound [for example] to LAX from LHR. If the track is through the midwest, typically speed restrictions and minor course deviations will commence in the Las Vegas area and sometimes well before that whilst the flight is still working Salt Lake or even Denver center. If you start hearing non-weather related course and speed changes inbound to LAX whilst over somewhere like St.George, UT its usually a fairly safe bet that flow control into SoCal/LAX is at the root of it. The restrictions will continue and sometimes get progressively more all the way to LA. Same is often true with speed restrictions well away from gateways like ORD, SFO and IAD - into IAD I've frequently heard ATC instructing inbound speed restrictions and course deviations prior to or in the NYC area, and inbound to SFO whilst still well up over northern Oregon or well before overhead Reno (depending on inbound course).
As has also been said, the US seems to hold domestic traffic on the ground at point of origin when significant congestion at a hub is forecast.
Long and the short of it is that the US typically has much more airspace to play with and ATC sequences traffic using speed, course and altitude restrictions far far further out from destination than can ATC in the UK where if they started slowing traffic out over the Atlantic they'd get some "interesting" backups and also potentially impact traffic into non-flow limited airports. Of course, pax are far less likely to notice a speed restriction than they are going round the racetrack at BNN or OCK, and its easy for the airline to announce a hold and blame it on ATC in London...
Andy
Last edited by EastMids; 4th November 2009 at 14:40.
Thread Starter
Joined: Apr 2007
Posts: 153
Likes: 287
From: Hawaii Island
Thanks to everyone for answering my question and especially to Andy (EastMids) for a most comprehensive response. I like to learn something new each day and I certainly did today. Thank you!
Tom
Tom
Joined: Oct 2002
Aviation Qualifications: PPL
Posts: 8,201
Likes: 347
From: London UK
Different places round the world have different approaches to the same issue. In the US you seem more likely to be just sent on an indirect slow track to while the minutes away, whereas at London they bring everyone in as far as they can and then do the "going round in circles" VOR hold, quite close in (from the Ockham hold you are in sight of the Heathrow runways). Each organisation has their own reasons why they choose their methods.
European airspace relies much more on following published routes, procedures and holds, whereas in the US they are more likely to give you radar vectors (ie individual heading instructions) to handle the flow.
At Hong Kong I was, unusully, put in a hold, which seemed to comprise overflying the airport and heading east out to sea about 50 miles, then turning and coming back. But at Helsinki (which gets surprisingly busy in the afternoon) it was a VOR hold just like London.
European airspace relies much more on following published routes, procedures and holds, whereas in the US they are more likely to give you radar vectors (ie individual heading instructions) to handle the flow.
At Hong Kong I was, unusully, put in a hold, which seemed to comprise overflying the airport and heading east out to sea about 50 miles, then turning and coming back. But at Helsinki (which gets surprisingly busy in the afternoon) it was a VOR hold just like London.
