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View Full Version : Changing runways around in light winds to accommodate incoming.


Julian Hensey
15th Nov 2007, 15:26
Ok three parts to this question for the ATC hard workers.

In light or no wind conditions with good visibility.

What is the quickest time you can turnaround the runway in use to accommodate aircraft coming in from different directions? What part of the process is the slowest part to getting it sorted?
Has there ever been a time when you were in the process of getting the runway turned around and you misjudged the incoming estimated time of arrival? :rolleyes:
Can you light both 09 and 27 for a departure on 09 while a 27 approaches (for example)? or is this a strict no no.Thanks!

radar707
15th Nov 2007, 15:30
1. As long as it takes to turn a key to swing the ILS and press a button to change the lights

2. No

HEATHROW DIRECTOR
15th Nov 2007, 15:37
But at a busy terminal it can take 30 minutes to an hour to change round as air routes in adjacent airspace might need to be changed, etc... a whole host of reasons.

anotherthing
15th Nov 2007, 16:43
Julian - your question is a little ambiguous (maybe intentionally so)... what type of operation are you on about? Different answers for different OPS.

You have said in light winds with good vis - if we assume a highish cloudbase as well, with no departures to go, then it can be done at the flick of a switch i.e. if for a visual to visual approach, one button switch to change the PAPIS from one end to the other... however, both the answers above are equally correct... just different levels of operation.

2. Radar 707 is not strictly correct - again depending on airfield setup and OPs. You could have Approach lights on for the arriving end, (say 09) with the runway uni directional lights on. The runway omni directional lights would light every alternate light as seen by an A/C departing on 27.

In the conditions you state, you would probably have a minimal or nil lighting requirement anyway.

Spitoon
15th Nov 2007, 17:02
Julian,

I presume you're talking about BRS. In good weather with the type of operations that go on many aircraft will be happy to make a visual approach - the PAPIs should be on but nothing else in required for a visual approach in good vis by day. Good practice suggests that the approach lights should also be on if visibility is in question. Likewise good practice suggests that if the ILS is not radiating for the landing runway the controller advises the pilot.

Most UK runways have high intensity bi-directional lights which have a low intensity omni-directional component. This means that they can be seen clearly on the approach to either end and will be visible from other direction at lower intensity - the main reason for this is to give aircraft in the visual circuit at night situational awareness cues - remember that these standards were developed when visual circuits were commonly flown by passenger aircraft (many of the ICAO standards originate in a time when DC3s were the typical aircraft type). I'm not sure what anotherthing is on about when he says alternate lights will be visible.

Many UK airports have interlocked switching of ILS and lights - because the CAA likes it. This means that you simply throw one switch to change ends but it limits flexibility. ILSs are almost always interlocked to avoid interference that would occur if both were radiating at the same time (particularly the localisers).

Bear in mind, however, that many aircraft operator's SOPs will not permit late changes of runway, regardless of the weather or other factors.

As for misjudging it - no, never. Having to revert to plan B, maybe occasionally.

Julian Hensey
16th Nov 2007, 08:26
BRS was one, although I am interested in other operations. For example last night the mail run to Edinburgh and Newcastle had to request from ATC to switch around to 27 departure as they were heading for Brecon on a Brecon departure - ATC sounded like they were planning to send them out on 09 which is longer track to turn back over to Wales - but that said - at midnight isn't there any mileage in co-ordinating with London Control and saying "these guys are going to Newcastle and Edinburgh, what about we send them off 09 and don't point them in the direction of Wales and see if we can get a more direct route?"

I am sure there are excellent reasons, but my "direct to" thread shows that it is possible to organise a direct to in the early hours :rolleyes:

WAIF-er
16th Nov 2007, 20:35
at blackpool, you can usually have any runway at any time if you can accept the wind. Have had a/c on finals for 10 and 28 at the same time... VFR of course!
:}

normally right blank
17th Nov 2007, 22:05
Have had a/c on finals for 10 and 28 at the same time
And keep right on landing! :ooh:

WAIF-er
19th Nov 2007, 12:29
it sounds crazy at first, but in practical terms, for light aircraft with say, one at 2 miles and the opposite one at 6 or 7 miles, its just another variation on cross runways operations (but without the cross runway at the end of the approaches!):ok:


PS. gets more interesting when one is a Hawk doing a practise ILS on 28!

britkit
23rd Nov 2007, 20:51
This practice is more common than you'd think, certainly at the smaller regional airports such as ourselves, where you've only got ILS on one end.
If it's light/nil wind (as in the question) then you can use whichever runway best fits the operation at the time, only being bound when someone wants circuits or an Instrument Approach.
The same is also true when you've got a cross-wind, which takes out the use of the 'in to wind end' (unless you've got a 'preferential runway' set up) as it doesn't usually matter for the bigger stuff. Frequently we'll have a bizjet or turboprop elect to land on the ILS equipped end in a cross-wind rather than visually manoeuvre for the non-precision end.
As for the amount of time it takes, it can be instantaneous, unless you've got traffic to deconflict.
Safety procedures are built into the ATC operation so that you don't get two aircraft speeding at each from opposite ends at the same time.

Jets R4 Kids
23rd Nov 2007, 22:52
Julian,
The problem with the 'direct to' with the specific night freight flights you mention is that they are deliberately timed to conflict with the inbound flights from Newcastle and Edinburgh !

Hence via Brecon or radar headings...


Rgds


J-R4-K