haughtney1
Point 1. You have simply restated that I want to know earlier, but haven't given any useful suggestions as to how this can be achieved. Point 2. This is really a question of semantics Giving you holding with a EAT is really no different to a feeder fix time + vectors/holding. |
I accept the reasons you provide... what I cannot accept is why I am so unlucky that just about every time I come to your country at least one of them is happening:{
|
Well someone used JFK as an example of one of the busiest airports in the world. Wikipedia shows the annual movement rate there is 410,000. They have two sets of parallel runways. Now compare that to Brisbane, which except under relatively rare circumstances is primarily a single runway operation with 226,000 movements in the last year. Now it should be easy to see that per runway Brisbane is moving more traffic than JFK and explain why you very rarely get no delaying action.
|
JFK has snow, icy runways, deicing, fog everything else the North Eastern US WX can dish up. Comparisons between movement rates between the relativity benign BNE weather & JFK don't make for a strong argument.
|
Do you know how this can happen?
Alright let's use KLAX as a comparison. Brisbane weather, but without the thunderstorms. 666,900 per year on 4 parallel runways. 166,700 per runway plays 226,000.
This isn't a di@k measuring exercise. I'm trying to give some perspective to those who seem offended when they receive delaying action at what they seem to consider airports with no traffic. |
This isn't a di@k measuring exercise. In you KLAX example again, what is the movement rate inside the LA basin itself? There are many fields in very complex busy airspace: LAX, Burbank, Orange County, Van Nuys, Long Beach - that covers just the major ones, all with jets. Again, not a valid comparison with any Australian field in terms of airspace & traffic density. "The System", not the controllers is the problem, and it could be fixed with more money, however there has to be sufficient will to make that happen. |
Do you know how this can happen?
Delays don't have much to do with traffic density in the vicinity, you don't get an extra lap just because someone is arriving into an airport down the road. What I'm trying to say with the LA comparison is it's all about the runway rate. We can move around 55 per hour on a good day per runway, which is up there with any airport in the world. If the demand is for more than that the delays build up.
The 250nm brick wall is fairly common around the world. Like has been said earlier, places like Heathrow will tell you at top of descent to expect holding. Why didn't they tell you to slow down 15 hours out? The technology doesn't really exist to achieve what you are looking for yet. Airways NZ is the first in the world to operate a combined ground delay / airborne flow manager that they designed them selves. I've seen the system operating, you can scroll through the whole day and look at the sequence of aircraft that haven't departed yet. But like has been said earlier it can only work with what it can see. An aircraft gets airborne three minutes late because the cabin wasn't ready and they had to wait for an aircraft to land in Wellington before they took off, now they can't make their landing time in Auckland and that landing slot is lost forever because everyone was slowed down 15 hours out to make room for them. For this reason they still only pass the RTA to the pilot 40mins from touchdown which would work out to be about 200miles. This game just isn't predictable enough to achieve what you want. |
Never fear all,
The promised land is visible on the horizon.... Have a look at this executive collection of buzzwords and catchy phrases. One Sky, the panacea that cures all ill's...... OneSKY Australia program | Airservices |
"By 2018, Australia will be providing air traffic control services using the most advanced and integrated air traffic control system in the world."
Now, anyone guess why this is probably true? |
Originally Posted by haughtney1
(Post 8986989)
Sure Will:ok:
2 things would be a good start. 1.Advise me in good time (being pragmatic here) of expected or planned delays... (Given I'm datalink equipped it's a few strokes on the keyboard) 2. In the event of a delay...do as they do in the UK and Europe and increasingly in the US, advise us, send us to a fix to hold, and give us an onward EAT. :ok: 2. What's the difference between that and us giving you a time that you can choose to slow down as much or as little as you want and we absorb the rest with vectors or holding? That's what I don't get. Why does it make you feel better to be given a 10 minute hold at 200 miles than us telling you to reduce speed to lose 10 minutes with the implicit understanding that you'll tell us what you want to do? There 2 things that would make planet haughtney better for me. P.S. If the controller is to busy, then isn't that an issue relating to safety and SA? It's called workload management. The system we use just isn't designed to work the way that you want. Sure it can be achieved manually but that is labour intensive so isn't going to happen when I'm busy. Are you guys understaffed or something? Knowing about a delay in good time also allows me to plan further on the basis of a contingency, prudence being what it is, my priority is also safety, knowing about that 10 minute delay in advance could be the difference between me legally being able to get to destination or divert. We can go back and forth as much as we like, I want this...you can only give me that etc..ultimately my neck is on the line everytime I plant my fat butt in the chair, yes you guys have enormous responsibility as well but your safety and well being is hardly an issue, to me when I hear "I'm too busy" it's the thin end of the wedge, what else one day might someone be too busy to pass on, you guys have that luxury, that safety valve, I don't. In an imperfect world we make do, we improvise and we get the job done, if you use system and workload practicalities as reasons for being unable to provide some basic information..then maybe your organisation needs to look at how others seem to manage. Not the guys on the front lines problem I know, god knows you have a bloody tough and thankless job at times, but as a team, we ought to be all moving in the same direction. Too idealistic? |
ALL Pilots should be required to do a shift in an ATC centre at least once a year that encompasses peak time, not the bull**** PR visit that you sometimes make now.
ALL ATC's should be required to a famil day, sitting in the cockpit for the full duty day that includes at least one flight at peak time into a major airport, not a single famil flight that doesn't see what the crew have to deal with for a full duty day. Guess why this doesn't happen now & will never in the future? |
Some great discussion going on in here! Although the original question seems to have been answered I'll throw in my 2c.
The way the sequence works in my neck of the woods is that the outer (ex) procedural sectors are responsible for for setting FF estimates into MAESTRO at around 350-400nm out, this starts to stabilise the system and then these controllers can give an expectation of delay and a Mach # slowdown when it hits a certain size. I'm not entirely sure what the process is for East Coast sequences re locking into MAESTRO, but for PH early stabilisation and slowdowns were what was requested by industry and works best for us due to the nature of the traffic patterns (no inbounds for 3-4 hours at a time, then a sudden sequence of 30-40 when all the mining traffic turns around at the same time). That's the reason that we have the outer sectors responsible for that stage. The next sectors (250nm out) are responsible for issuing the actual FF times, making sure MAESTRO has put aircraft the correct order (remember the original sequence is built off pilot estimates.. Which is why MAESTRO often tries to put the cheeky bugger in his F100 ahead of the 737 even though he's 20nm behind and 20kt slower). Even at this stage your 'expect a 6-7 minute delay' may have blown out to 15 mins due to 3 departures from nearby aerodromes. I guess the reason these departures aren't all allotted times in the sequence before departing is that if they don't get away on time then there will be holes in the sequence and everyone gets punished as a result... Similar to when pilots give an unrealistic estimate for JULIM, become number 1, then despite getting direct and pushing 310 on the descent to JULIM they end up 2 mins late and every behind gets shafted... From 250nm to 160nm pilots have the chance to let us know how close they can get to the issued time and this info helps the inner centre controllers figure out the most efficient way to achieve the rest.. The last 12 months, with the implementation of MAESTRO and the consolidation of the GDP, has seen a decent increase in the number of aircraft being able to achieve the delays without our intervention. We've gone from 20-30min delays + holding the majority of traffic twice a day, every Tuesday/Wednesday/Thursday to occasionally having 15-20 minute delays and maybe holding a couple of aircraft a week. But to go back to the original post there are still some instances where we will have to hit someone with 10 or so minutes on short notice.. People have discussed go arounds, medevac, rwy changes etc.. But occasionally it will also just be a case of taking a little longer than usual to pick up the delay. An example is: at 400 miles you give your estimate which puts you in your own sequence.. No one in front of you for 4-5 mins and no one behind you for the same time. Procedural sector locks this in, sees no delay in maestro and moves on to their next job. You get transferred at 250miles, get your STAR, and still no delay in MAESTRO, and no one near you so your time at the fix is not pertinent. In the next 6 minutes 3 departures get away from 2 aerodromes within 100 miles, and someone finishes airwork and is ready to return. These aircraft all need to be sequenced and some will end up in front of you.. Chances are you are coming in from the north and all these departures came from the south so it's a different controller looking after them. Someone who is all over it will be aware of what's going on in surrounding sectors, assessing Maestro making sure all times are up to date, but it does happen occasionally that as per this example an aircraft might run through to 160 odd miles before the inner controller picks up that what was originally a sequence of 1 has become a sequence of 4 and your dreams of scooting through the terminal before the rush are shattered. |
Thanks for the detailed explanation WhisperSYD. :ok:
|
Do you know how this can happen?
Generally speaking should say the wind be calm, you're cruising at FL400 in your 77W. You're 200nm to run and have been asked to lose 10 mins. I'd imagine you're pretty close to min speed already at FL400. My question is would you rather stay at that altitude and speed and take a lap of the pattern, or descend lower to reduce the TAS and maybe take what you can 't lose with a vector. Technically speaking what would be more efficient. As soon as you've been assigned a delay you're now flying for best endurance instead of range. Is the best endurance going to be at mid levels as opposed to way up high? Or is it more efficient to stay high?
As a side note I was amazed on my last famil flight which was on an A388 from Auckland to Brisbane. Cruising at FL4XX at what was probably M.84 or so and 260 odd indicated or whatever it was and were assigned a delay of 15 minutes. I was very impressed at how slow the A388 can actually fly, we slowed down to about 210kts IAS and started a gradual descent for next 100nm or so. Still needed a lap of the pattern but it surprised me how flexible that aircraft is. |
As a side note I was amazed on my last famil flight which was on an A388 from Auckland to Brisbane. Cruising at FL4XX at what was probably M.84 or so and 260 odd indicated or whatever it was and were assigned a delay of 15 minutes. I was very impressed at how slow the A388 can actually fly, we slowed down to about 210kts IAS and started a gradual descent for next 100nm or so. Still needed a lap of the pattern but it surprised me how flexible that aircraft is. On my machine fuel burn (including 5% allowance for racetrack hold) burn at altitude vs holding at 1500' 10,000' -4% FL200 -7% FL300 -7% FL350 -6% There isn't any benefit staying high to hold. By holding in a straight line you save 5% right off the bat. In general I find I only burn half the holding fuel by descending to say FL250 vs continuing at flight planned cruise altitude then entering the pattern to lose the same time. Slowing down at optimum altitude doesn't lose much time, due to relatively high minimum speed. Each aircraft will have its own profile, twins need to consider engine failure at min speed at high altitude, not so critical for an A380. PER seem to have a good system, you blast off heading south, pass an estimate for JULUM, ATC get back with a crossing time and you use the next hour or two to lose the time, 15, 20 or even 30 minutes is possible with sufficient notice. |
I am going to answer inevitable question. Why can it be done in Perth but not in Sydney and Melbourne?
The vast majority of jet traffic for YPPH departs from outside 400nm YPPH. This means that a sequence generated for an aircraft at 400nm is going to be a reasonable approximation because it is less likely to be changed by another jet departure closer to YPPH This is not the case for YSSY and YMML. http://i57.tinypic.com/mlla10.gif As you can see every departure from YSSY, YPAD, YSCB and tasmania is within 400nm of YMML. Similarly for YSSY. Every departure from YMML,YSCB,YBBN is within 400nm. This is why we have to wait till you are about 250nm for the sequence to become stable. |
WhisprSYD,
Thanks for the great detail you went into with your explanation, helps us understand things a bit more. . Which is why MAESTRO often tries to put the cheeky bugger in his F100 ahead of the 737 even though he's 20nm behind and 20kt slower). Cheers, TL |
Originally Posted by angryrat
(Post 8988316)
To the ATCer's on this thread, thanks for the great job you do day in day out. Yes I admit I've sworn under my breath at you most days but it has never been personal and is more out of frustration than because of the job you are doing(I'm sure you have done the same with me). Like haughtney I get frustrated with the late notice, however, I get it is the system and I'd rather be given the option of losing that time myself than just being sent to a hold.
Whatever you guys do please don't punish us all because of one airline. By all means send planet haughtney and his airline to the hold every time they need to lose time. Please let the rest of us make the situation work and beat them on efficiency. Since the ground delay program and this airborne strategy has been introduced, I have had to do very little holding in Oz. In fact we managed to lose 12 minutes without a vector into BNE the other night and yes we could hear the doubt in the controllers voice as to whether we would make it or not. Yes we had to work harder to make it happen but I believe that we saved my company 800kgs of fuel in one sector while some others just bleat. On average that means someone gets screwed for the benefit of the greater good. Better luck next time? |
Originally Posted by Transition Layer
(Post 8988960)
WhisprSYD,
Thanks for the great detail you went into with your explanation, helps us understand things a bit more. Glad to hear that you are aware this stuff goes on. Very frustrating for us too, as we know exactly where he/she is thanks to TCAS and we all know a 737 cruises faster than an F100! Cheers, TL Yeah we try and police it to the best of our ability, and the fact that we can see exactly where all of you are on ADSB helps spot the obviously 'ambitious' estimates... It also used to be a pain in the ass switching aircraft around as it involved lengthy conversations with the flow, but MAESTRO has given us the license to use a bit of common sense in that situation. That being said, it all comes down to the controller working too. Some of the newer, fresh faced and recently rated controllers still take a pilot's word as gospel, whereas those of us who have been around for a little longer have learned to be a bit more cynical when it comes to trusting all FF estimates. |
Similar to when pilots give an unrealistic estimate for JULIM, become number 1, then despite getting direct and pushing 310 on the descent to JULIM they end up 2 mins late and every behind gets shafted... I'll be honest, I don't understand why, in this age of technology, you need to be relying on a verbal fix estimate. However, why not give aircraft unable to make their fix time a 180 degree vector to the back of the queue - I reckon that might sort out the problem. |
All times are GMT. The time now is 22:17. |
Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.