Hi Liam
You come up with some useful observations. What happens now:
1. The two AMC's (N and S) will be watching things and trying to get a feel for the best option. EIther to change runways or stay put.
2. They'll discuss with the Tower supervisor that a Runway change is either: (a) A good idea, or (b) a necessity.
3.If it's the latter, then it happens immediately and everyone just has to live with it. If there's some flex in it, the tower supervisor will ring to Approach supervisor and say: "wind seems to be favouring (new runway) let me know what you want".
4. At this point the tower co-ordinator will generally give a heads up to the Delivery person and the Ground controllers along the lines of "Hey guys, (possible/definite) runway change (likely/imminent).
5. THe Approach cell are the major determinants of when the last landing will occur. This may be in 10 minutes (a quick change) or in 40 minutes.
6. Meanwhile, the delivery person will generally give a heads up to possible effectees. This is not always possible because of the unknown time frame from the Approach cell.
7. ATIS reflecting the new runway will be prepared but often not actioned until the last minute. Bear in mind that it takes time to prepare the ATIS and for the tower assistant to record same. This is even more time consuming during periods of particularly inclement weather when many changes are taking place.
8. The Approach cell will advise the tower co-ordinator, of a "Last lander on old runway" along with an expected landing time.
9. FRom this, a clearance expiry time for the last departure off the "old" runway will be agreed normally about 6 minutes before the last landing takes place.
10. Meanwhile the GMS (Ground South) pretty much has a final say as to who will be the last "old runway departure" though often there will be mutual discussion between the AMS/Supervisor and GMS.
11. When it's been decided, then Delivery and the relavant GMC's will give updated SID's.
12. Me personally, as soon as I hear of an impending runway change and I'm on Ground, I like to give out what I think is a good guess to impending departures as to what to expect. THis is not always possible due to the variable time frame that Approach may take to decide the "last landing".
13. Worse case scenario's are an immediate change with little or no lead in time, such as mentioned by the Baron man, and we just have to turn everyone around and go to the new runway. This is bound to happen, when due to weather deviations in Departures airspace and we have say 4 minutes departure flow, there will invariabaly be a long queue at the old threshold that will need the new runway...and yes...sometimes with a downwind component at the start point.
Sorry to be so long "winded"
Last edited by Bedder believeit; 24th May 2012 at 23:21.