Sydney Winds - What's Going Go?

[Capn Bloggs]

The ABC website says that International flights are running normally; the winds are only affecting domestic flights.

Are our domestic pilots less capable of operating in 60kph winds than internationals??

[big_head]

With the reduced acceptance rates I assume the domestics would consolidate/cancel flights instead of the internationals....

[AerocatS2A]

That would be my guess as well. Much more flexibility in the domestic network.

[roundsounds]

With reduced capacity (single vs two runway ops) it's easy to understand why the operators of the airport and Airservices have used the criteria they have to determine who gets slots and who gets parked. International ops tend to use heavier aircraft - movement fees are based on weight. Bigger aircraft = more $ - pretty simple.

[AerocatS2A]

Meanwhile those that fly in during the curfew just have to accept the crosswind ;).

[L'aviateur]

Very similar practice in the major airports in Europe, short haul flights are curtailed to provide for the long hauls in the same circumstances.

[halas]

Years ago out of Nice they shut one runway due turbulence.
FFS they are less than 300m apart!
It was very windy, but it was the day after the Monaco GP and the Cannes film festival and the most movements in any day of the year.
3hr delay to Fiumacino only to find the same low pressure system there and only rwy 25 in use. FFS!

halas

[Beer Baron]

Domestic flights to SYD are subject to departure slot control. With reduced flow the earliest slot your company can get may be 3+ hours away, hence it makes more sense to cancel the flight and consolidate the pax on other same-day services.

Not a practical option for an international 777 or 380.

[4 Holer]

Worlds best Babies...

[Square Bear]

"...but international jet aircraft have priority over domestic jet aircraft"

Don't think so.

Besides some management and economic benefit reasons that may be applied,(and your AIP List) I think you will find that it is first in, first served, with scheduled commercial air transport and non-scheduled air transport having priority over general aviation.

Beer Barons post makes more sense.

"Jet aircraft also tend to have lower minima than turboprops."

Bit of a generalization there!!

[josephfeatherweight]

IMO, there was no requirement for a reduction in capacity yesterday at SYD. The wind wasn't that strong, was it?? We landed on 25, early afternoon - not even anyone lined up at the holding point waiting for departure - though I know this was not peak time.
16L+R could have been used all day for departures, surely?
Anyone know what the max crosswind was during the day??

[*Lancer*]

Most aircraft have crosswind limits between 30 and 40 knots don't they...?

What's the problem?

[big_head]

Most aircraft have crosswind limits between 30 and 40 knots don't they...?

What's the problem?

The 20kt crosswind limit imposed on runway selection. If 30kts is a safe crosswind to operate with then push for change. ATC certainly do not go from 2 to 1 runway for the fun of it.

[Aussie Fo]

40 kts is roughly 20 meters per second.

Runways are generally 45 meters wide and obviously we land in the middle.

Your complaining about a couple of hours delay because someone with 1000s of hours experience has decided a little delay is a good offset for being off the runway in 1 second if it doesn't go well.

Take a look at you tube. I can attest I've been in 35 kts in Adelaide once in my career and it isn't pretty.

As far as ATC are concerned I think these days airline rather cop the delay in the ground rather than a hours holding

[ramble on]

How many movements per hour is the single RWY 25 limited to in order to meet SYD airport noise compliance?

Is it 40 or 80 movments per hour on a single runway? Were movements slowed below that of a normal fully manned capability due to noise restrictions or controller capacity?

[CurtainTwitcher]

Yesterdays effort, 5 minute legs with track mile markers (nm) giving an indication of distance travelled in the hold.

https://i.imgur.com/JedmEaV.jpg

[clark y]

And will curfew be relaxed to clear the backlog?

[Deano969]

How many movements per hour is the single RWY 25 limited to in order to meet SYD airport noise compliance?

Is it 40 or 80 movments per hour on a single runway? Were movements slowed below that of a normal fully manned capability due to noise restrictions or controller capacity?

Very good question

Another good question is why are they building BCA in stead of a second east west runway at KSA
Even if it were just a 1800m runway or less just for regionals or a longer "take off only" runway so that there was an allowance for strong crosswind on 16/34

[neville_nobody]

Why was 20 knots considered the limitation? Given the chaos that results maybe that number should be higher or at least allow people to land on 34/16 if they deem it acceptable.

[big_head]

The 80 movement per hour cap applies, regardless of the runways in use. It can't be hit on a single runway (mid 50's is a rough max). No idea where the 20kts comes from, ICAO maybe? utilizing both 34/16 and 25 for arrivals and departures doesn't really increase any movements, it would likely do the opposite as complexity increases. A 25kt limitation would likely eliminate a high % (80 at a guess) of 25 only days. 30kts would almost eliminate it altogether. Whether that's considered safe and would get signed off is another question.

[CurtainTwitcher]

And will curfew be relaxed to clear the backlog?
It was :ok:

[clark y]

Wow! You mean the curfew can actually be eased to allow for "acts of god". Probably took an emergency sitting of parliament to do it pushed by SACL complaining about lack of revenue caused by reduction in movements.

[AerocatS2A]

Dispensations are occasionally given though I believe they cost a bit of money. You still have to use the curfew runways during curfew though, so if the wind doesn't allow for take-off on 16R, you're out of luck.

[mustafagander]

Another thing to keep in mind with regional flight cancellations is the destination winds. Think narrow runways and 25Kt xwinds. Sometimes the departure is not your problem.

[Bula]

Aussie FO, perhaps you want too recalculate that brilliant load of tripe to allow for the relative velocity of the aircraft for apparent crosswind. I hazard a guess your calculations might be slightly off by a fair bit. 67% percent of the time, all the time logic.

20kt crosswind for runway preference is a little crazy, but I respect the fact that the into wind runway does have its advantages in allowing for Sod's law.

I feel the procedures need to be changed to allow operations on the other runways should the PIC make that request.

[Bug Smasher Smasher]

Another good question is why are they building BCA in stead of a second east west runway at KSA
Even if it were just a 1800m runway or less just for regionals or a longer "take off only" runway so that there was an allowance for strong crosswind on 16/34
Ha! Where would you propose they build this? In the middle of the Bay? :rolleyes:

[Capn Bloggs]

Aussie FO, perhaps you want too recalculate that brilliant load of tripe to allow for the relative velocity of the aircraft for apparent crosswind. I hazard a guess your calculations might be slightly off by a fair bit. 67% percent of the time, all the time logic.
Coming to the seat on your right soon...

Ha! Where would you propose they build this? In the middle of the Bay?
As happens elsewhere?

[Bug Smasher Smasher]

As happens elsewhere?
Sure, but this is Australia. Yesterday's infrastructure tomorrow. Maybe. But probably not.

[Biatch]

Considering the max component is upwards of 40knts for most aircraft, increasing the limit from an average of 20, to an average of 25 or even 30 before single rwy ops are enforced in my opinion is more than reasonable. Everyone I've flown with over the last week has been dismayed that the line is so conservative. Whilst we do usually go for more conservative options in flight , this seems excessive.

[PW1830]

How many aircraft have 40+kt xwind certification??

[Capn Bloggs]

How many aircraft have 40+kt xwind certification??
Biatch said "upwards of 40"; that means approaching 40.

increasing the limit from an average of 20, to an average of 25 or even 30 before single rwy ops are enforced in my opinion is more than reasonable.
Agree. FDAP will have a field day though...

[Jetsbest]

Biatch said "upwards of 40"; that means approaching 40.

Er.... NO! In my upbringing such a phrase, put another way, meant 41 or more.

I'm with PW1830 on this! ;)

[Capn Bloggs]

OK, just checked, my GGS English is not as good as I thought. Point taken!

Let's say the "max demonstrated crosswind is 38kt". That makes Biatch's idea quite plausible.

[VC9]

Give me the 25-30 knot crosswind on runways 34L&R any day in preference to the mechanical turbulence on runway 25.

[Keg]

It'd be interesting to see how it worked in practise with winds north of 25-30 knots. With a 240/30 gives 3 knots downwind on 34L. 250/30 gives 3 knots headwind. So I'm not accepting 16L when I'm likely to face what is likely to be at least 6 knots undershoot or overshoot on top of the crosswind and potential downwind. I'd be very surprised if there were many other heavy jet drivers who would. Never flown the 737 so can't speak for those drivers.

So already we've started to reduce the capacity of the airport by putting most jet arrivals onto the long runway.

Mechanical turbulence on 16R approaching the flare with the wind at the 220-240 degree mark would be diabolical too. I wonder how many go-arounds that may generate further reducing the runway capacity.

Anyway, something to consider.

[RAC/OPS]

How on earth do they manage overseas with parallel runways and no crossing rwy?

[Keg]

LAX doesn't get northerlies. ;) :D

[missy]

The current 20kts runway nomination criteria came about because QF 767 drivers pushed for it, plain and simple. It could be 15kts, it could be 30kts. ATC don't care but play by the rules. The problem is that there can be 15kts at the northern end of the field and 30kts across the bay, therefore 25 only.

If the pilot union(s) want a higher crosswind criteria then have a word to CASA.

[PW1830]

Spent a long time on the 767 from intro on- nothing to do with us entirely. Probably something to do with the Minister of Aviation - Brereton I recall - forbidding the use of 07/25 that involved his electorate unless extreme circumstances. Saw some ugly scenarios with his policy.

[severidian]

Runway nomination is not at ATC discretion it's in the regs.
Curfew dispensation at the ministers discretion.

[PW1830]

Regs were changed to comply with Breretons view on how an airport should function.. Howard had his input too.

[Keg]

Spent a long time on the 767 from intro on- nothing to do with us entirely. Probably something to do with the Minister of Aviation - Brereton I recall - forbidding the use of 07/25 that involved his electorate unless extreme circumstances. Saw some ugly scenarios with his policy.


Agreed. In the late '90s we were having to do stupid stuff like land on 07/25 with 20 knots crosswind and 5 knots tailwind. Or similar with 16L. Sometimes we even had to hold for the privilege of landing on the single, short, runway with tailwind, simply because the time of day specified which runway Config should be used.

AIPA put out a directive to not accept more than 15 knots crosswind when it was being applied for noise sharing. Note the important distinction there? We'd happily accept 20knots if it kept the flow moving. We wouldn't accept it simply because the time of day specified we had to when a more efficient into wind configuration was available.

[Derfred]

I have no expert or inside knowlege, but I do know that MEL applies exactly the same XW/TW wet/dry as SYD, so I seriously doubt it is politically driven or airline driven. Probably closer to the truth would be ICAO standards.

Yes, AIPA did issue such a directive many years ago, but that was a response to political noise sharing (exactly as Keg said). It never had any influence on SYD airport modes to my knowledge.

[missy]

AIPA did issue such a directive many years ago, but that was a response to political noise sharing (exactly as Keg said). It never had any influence on SYD airport modes to my knowledge

Yes it did influence the mode operated as the requirement to land 16R often led to a change back to parallels ops.

The XW criteria was 25 knots, its now 20 knots. As I said it could be 15 knots or could be 30 knots. Its up to CASA and I guess the airlines. Increasing the XW criteria "too high" could lead to more off-mode requirements which have safety and efficiency considerations. Examples - landing aircraft requires RWY 25 when operating 34 parallels.

[PPRuNeUser0182]

So what happens somewhere like Brisbane when the crosswind is 21+kts? Close the airport or just deal with it as per the training and aircraft capabilities?

What happens around the rest of the world?

[sunnySA]

When the crosswind is 21+kts?
Quote the wind and get on with things, however when there is an alternative runway with 20kts or less then quote that runway.