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B A Lert
12th Apr 2006, 03:28
With the cost of a barrell of oil now approaching US$70 with flow-on to aviation fuel, one has to wonder if any of the bureacrats or, dare I say, politicians have given any thought to the impact of noise abatement to the airlines costs?

Today in YSSY, RWY 34L & 34R were being used with the heavy jets departing from 34L. Emirates, running several hours late, operated an A340 YSSY to NZCH and headed way out west for about 15nm and then made a sweeping left hand turn to set course over the SY VOR to NZCH. Why couldn't that flight have continued on RWY HDG for about 10NM and then make a RIGHT hand turn to set course for NZCH. Surely it is possible to do this, maintain separation with the lighter jets and bug smashers using 34R and thus minimise the ever increasing operational costs of the airlines?

SM4 Pirate
12th Apr 2006, 06:12
For every SID there is usually a conflicting STAR or arrival; it's not the 34R departures that get in the way although it is considered; it's the 34L&R arrivals from the North. Cross overs happen and are considered in SOPS.

The route you describe isn't the stuff of a mad ATC; it's the SID from 34L to the East... KLAX, PHNL and NZ deps get it every time they leave from 34L.

Standard OPS is far easier to follow for all concerned than make it up at the time stuff; SOPS should also enhance the safety; 6 mins of fuel is far less costly than an accident.

Sometimes you are the statue, sometimes you are the pigeon...

DirectAnywhere
12th Apr 2006, 06:25
I disagree SM4.

Aircraft inbound from the north (and east) are held at 6000' until abeam the airport to allow for departing aircraft off 34R to make their noise abatement departure (a hard right turn - thinking the MARUB departure) and climb to 5000'.

There's no operational reason aircraft off 34L can't climb to and maintain 5000' straight ahead to 10ish miles and then turn right. Once clear of inbound traffic at 6000' - continue climb. I know 'cos I've done it. The only problem is it pi$%es off the locals in Manly, Fairlight and Mosman (and one bloke in Kiribilli) and they're the ones with the education, money and lawyers to advocate for a change in departures. (NIMBY).

There is no logical reason the Richmond Departure should be the normal SID for aircraft departing to the east that are too heavy to use 34R.

In short, it's a crock that's pedalled for the purpose of political expediency.

B A Lert
12th Apr 2006, 07:16
SM4Pirate - I'm not concerned about late running flights making time but the cost of the additional fuel when a more sensible SID may be employed. It is true that the heavies to KLAX and KSFO generally proceed on a runway heading and turn right when 6 or 7 miles from the airport but for the likes of Air Canada and Qantas to PHNL, anyone going to New Zealand, Fiji, Tahiti or to other points in between invariably enjoy a scenic tour of north-western Sydney before being able to turn right or left to set course. While a rwy heading/right turn saves time you cannot deny that it costs money. If a daily YSSY/NZCH had to depart as Emirates did today, and fly an additional 6 minutes, a conservative number, then the annual additional fuel usage would exceed 350 tonnes - enough to fly a B744 to EGLL and half way back. It all adds up!


With the modern radar and communications facilities available, can't the ATC 'architects' devise safe and sustainable SIDS to conserve resources, and save money? That they create a bit more nuisance for some of the better-off in YSSY should be beside the point.

Note, dear SM4, that those at the coalface are not the target of my gripe as they just have to do as they're told but perhaps they can think about matters as have been raised in this thread and then rattle the cages of their leaders/management? Maybe such a new SID could be named NIMBY :ok:

SM4 Pirate
12th Apr 2006, 08:05
In reality B A Lert; the real question is why is the movement rate 'capped' at 80 an hour?

I read somewhere that at conservatively the TAR/concrete available in the SY layout could easily do 105+ per hour, probably 120; without any significant increase in risk (in parallel modes). From my perspective we put them further apart than we used to do, to ensure we don't break 80...

That would be a better question than the specific target of AKL, FIJI, CCH departures from 34L.

nomorecatering
12th Apr 2006, 08:45
More to the point, why do we still have the archaic 250kts below 10,000 ft law. Departures would be able to clean up and accelerate to a more ecconomical speed early, and get out of the terminal area a lot quicker, minimising noise.

Even more rediculous, the arrivals on their long dwnwind legs, speed having to be below 250 kts, more often than not with lots of flap out and engines at a much higher than idle setting. burning gobs more fuel and noise.

Why not allow them to wistle in at their best speed, around 300-320 kts, engines at idle like they used to. The noise level on the ground is noticeably less.

Heard all types of reasons, turning radius for sids and star, etc etc. Sounds more like official bulldust to me.

Frink
12th Apr 2006, 12:25
Hey Mr Lert, if you're thinking of abandoning noise abatement for the sake of operational efficiencies to the airlines, then I think you've picked a pretty weak example. Your suggestion helps about half a dozen flights a day. And that's only on the days where 34 is in use for departures!

How about trying to fix the situation where every single arrival for several hours a day cops up to a fifteen minute airborne delay, just for the privelege of landing on a less safe, noise sharing runway (usually with excessive cross and/or downwind)? Good luck! ;)

Centaurus
12th Apr 2006, 14:06
Nomorecatering. Interesting to note that 250 knots IAS is usually the maximum speed with window heat inoperative because of the danger of bird strike on a unheated rigid windscreen. This must tell you a story?

"whistling" in at 300 knots plus at low altitude where bird strikes are possible makes a bird strike at those speeds potentially disastrous - keeping in mind the TAS is what kills you in a bird strike. I have seen the effect of a seagull strike at 160 knots smack on the windscreen which took out the pilots eye.

It's marvellous fun rocketing along at 320 knots in a jet over the coast at low level below 3000 ft - until one day or night a bird fails to see you in time. Murphy's Law dictates it will go straight through your windscreen and leave you without a head.

Guppy Driver
12th Apr 2006, 14:18
I concur with everything Centaurus has said and would like to add that in addition to the feathered variety flying below 10000', there are also the possible consideration of collecting an Indian through your windshield (that is a Cherokee, Apache, Saratoga, 172 etc) - OK, that last one might not be an Indian, but you catch my drift.
Guppy

Led Zep
12th Apr 2006, 15:47
Mind you, Guppy, I'd just as rather hit another aircraft mid-air (God forbid) at 250kts as I would at 50kts. The outcome would probably be just the same! :eek:
Although I do concur that the slower you go, the more time you have to see and avoid. :ok:

Guppy Driver
12th Apr 2006, 21:33
You are right Led Zep, whether you hit someone at 50, 250 or 300 is rather academic. It's just that for the obvious reasons - oxy-requirements for non-pressurized aircraft, anemic piston engines, proximity to the scenery and airfields etc. - there are a lot more Indians close to the ground tham at the Flight Levels. I'll admit that the regulations are not perfect in this sense, but I reckon 250 does offer an added level of safety vs. "whistling in at 300-320 knots at low altitude". My argument will obviously be weakened if ADS-B becomes mandatory, but Centaurus's stand until the Birdflu has wiped out the lot of 'em (..................or the lot of us come to think of it, in which case this whole argument REALLY becomes academic;)).

UnderneathTheRadar
12th Apr 2006, 22:20
Mind you, Guppy, I'd just as rather hit another aircraft mid-air (God forbid) at 250kts as I would at 50kts. The outcome would probably be just the same! :eek:
Although I do concur that the slower you go, the more time you have to see and avoid. :ok:

Hmm - traffic at seen at 1 mile gives you 14.4 seconds to react @ 250kts and 11.3 secs @ 320kts ignoring any closing velocity. That's why the big boys have TCAS!

duknweev
12th Apr 2006, 22:21
Runway heading 34L/Right turn: Blame the Q. ATC can do this where traffic complexity dictates, although with simultaneous fanned turboprop/jet departures of 34R it becomes pretty tricky unless you can maintain the 34L departure at 4000'. Q said they can't maintain 4000' on departure except in emergency. When Nth American departures require the right turn, ATC will normally hold all 34R departures until the 34L is 10 miles upwind. Great efficiency gain? Directanywhere - there's also a Terry Hills resident affected by these departures, but I think he likes jet noise. An upcoming airspace redesign is in the works and this may improve the situation, but it is primarily designed for relaxing requirements on arrivals to the expense of "screwing" the departures... something Q was quite happy with.
250kts: for jets departing in the "wrong" direction (eg 34L for the SE, 16R for the NW), best rate of climb is needed to get to 10,000' above the inbounds. Apart from that, high speed is normally not a problem. For arrivals, blame Q. With all their jets doin' economy 265kts, the whole lane slows down.
Frink hit the nail on the head... the odd inefficient departure is nothing compared to legislated LTOP delays. Write to your local member :8
Movement rate: With the number of heavies at SYD, I reckon it would be hard to get to 100/hr. I think 90ish was achieved once or twice (the limit is the metered rate, not the actual rate). Some limitations include ATS procedures which restrict the arrival spacing to 5NM in the 34 direction, 4NM in the 16 direction, to get a departure in every arrival gap. There are efficiencies to be gained here with correct technologies. LTOP restrictions on the use of 34R/16L often cause much greater delays on 34L/16R than would otherwise be the case. Also, blame the Q... seems to be more and more of their crews "requiring" the long runway with over 15kts xw, blowing out the system-wide delays. What's the deal?
Bottom line, SYD is constrained by local residents and their political representatives. Damn democracy, don't you hate when it gets in the way of good business? I'm sure a quiet word into the ear of Macquarie will get their attention. Either that, or jack up the surcharges on the punters, and call it a "Sydney Noise Abatement Surcharge".

Centaurus
16th Apr 2006, 05:06
SYD is constrained by local residents and pollies. Dead right about that. It has been like that for decades. Back in 1969, residents under 07 glide slope 5 miles from threshold bitched about aircraft noise (DC3's, Viscounts, F27, and jets of various types). Word sent down to Head Office DCA in Melbourne via pollies to do something or votes would be lost. Over cups of morning tea in DCA suggestion was made by a minion to increase the GS angle from 2.75 degrees to 3 degrees. This gave an extra 150 feet or so over the OM and noise footprint would in theory reduce by miniscule amount due less thrust needed to hold 3 degrees. Pollies were happy because they could tell their voters they had reduced the noise. Of course there was no noticeable difference.

It then cost tax payers lots of money to raise the GS of all other ILS around Australia and have them flight tested by DCA DC3 and F27 calibration aircraft. Then someone said what about the T-VASIS? After all it wouldn't be a good thing if VASIS should also be set to 3 degrees to ensure standardisation with the ILS installations all around Australia? Now DCA had a tiger by the tail. So more big money was shelled out for the calbration aircraft to up the VASIS everywhere. Then voila! ICAO thought Australia had set a fine example for the world to follow and promptly published the new standard of three degrees for electronic and visual glide slopes. All for so called noise abatement.