Traffic congestion/Air traffic

[Tony G]

Just got back from a Singapore trip from Sydney via Melbourne. One thing I noticed was on three out of the four legs we had been delayed due to traffic build up. So we had been put into a holding pattern for a while on all three legs. I did notice with the Melbourne delays, it was put down to only having one runway in operation. Sydney and Singapore was due to traffic build up.

I know this is not a desirable way to operate and there are windows for airlines to complete their flights however it seems with any delays for any reason it opens up the potential for aircraft to be in a holding pattern at the other end.

Not sure if this is the sign of the times with aviation or I was just unlucky.

[Matt_L]

Tony,

Melbourne has notorious holding patterns at the moment ( usually mornings when the traffic esp Intl is highest ) with runway 09 27 out as you said..

In terms of it across the board- delays and holding patterns are a part of air travel and always will be- look at London for example with the stacks - you can't filter 1500+ flights through all on time..

Sydney has a increasing number of flights and this only adds to the problem ..

[Adam P.]

Airlines tend to schedule according to the 'best case' - good weather, all available runway slots used. So when something happens to reduce that 'best case' - weather, runways out of service, whatever - delays will occur.

For example, two runways at Sydney will produce a landing rate of (say) 50 aircraft an hour. If 45kt westerlies mean that only RWY25 is available, the available rate might halve to (for example) 25 aircraft an hour. But if there are 40 aircraft scheduled to land in that particular hour, there are 10 aircraft that now need slots in the next hour... but if that hour is over capacity too, the delays quickly cascade down the line.

Numbers are approximate based on what I remember of my previous job... but hopefully you get the idea.

Adam

[D Chan]

the situation in Melbourne has been quite bad due to the runway works - though there's nothing the airlines can do... I have heard of queuing times of up to 1 hour when it gets bad. Wouldn't be surprised if taxi times could at times get worse than that.

[Matt D]

Is Sydney constrained the cap of 80 movements per hour or something else?

80 movements an hour in Sydney shouldn't be an issue unless weather rules out the parallels.

[Philip Argy]

Slightly OT but I thought people would like this if they haven't already seen it:

http://www.youtube.com/watch?v=z1US_...layer_embedded

[Chris W]

Recently a bit more per hour
There have been instances recently where the 80 cap has been exceeded when delays in one hourly bracket force a couple of arrivals into the next hour. I imagine it would be incredibly hard to monitor and enforce.

Most of the holding in Sydney over the past two weeks (and there has been a lot of it) can be attributed to 16L ILS (i think) being out for maintenance and poor weather. So ATC have to place a greater distance between arriving aircraft when visual approaches cannot occur.

[Mario Facchini]

Originally Posted by Chris W

Most of the holding in Sydney over the past two weeks (and there has been a lot of it) can be attributed to 16L ILS (i think) being out for maintenance and poor weather. So ATC have to place a greater distance between arriving aircraft when visual approaches cannot occur.

According to ATIS, that was the case this afternoon,

RWY 16L GP & ILS DME NOT AVBL, DO NOT USE FALSE INDICATIONS POSSIBLE. PARL RWY OPS IN PROG. INDEP DEPS IN PROG.

[Tony G]

Originally Posted by Philip Argy

Slightly OT but I thought people would like this if they haven't already seen it:

http://www.youtube.com/watch?v=z1US_...layer_embedded

WOW, That happens everyday... Alarming when you see air traffic on a global scale. There has to be environmental effects from this. Yeah I know a contradictory statement from an aircraft spotter

[D Chan]

Originally Posted by Mario Facchini

According to ATIS, that was the case this afternoon,

I assume this is an airservices australia issue? this wil end up costing airlines and SACL