Twas my second thought, right after my WTF? moment.

Come on Bloggsy..jealousy will get you nowhere....how big is a 717 again? :}

(at least thats what I think you drive...:ok:)

Yes, yes, yes, I know, your centre tank holds more fuel than I weigh!! :{

At least you have one of the quietest cockpits made, very nice.

Maestro works by using untouched landing times of all the arrivals - basically the system estimate for the fix plus the time it calculates (to the second I believe) you'll take from the fix to run around the STAR to the threshold. The sequence is simply the order of untouched landing times. This isn't set in concrete until quite late in the piece so you can jump around a bit at times.

It then takes the acceptance rate (time between arrivals), spaces the sequence accordingly and calculates landing times. It then calculates your time for the fix so you land at the required time.

Meaning if you get several aircraft with very similar untouched landing times it's possible to go back (or forward) several spots if estimates change a little. i.e. you can go from 0 delay to 10 minutes just like that. 10 minutes would be unusual but it's entirely possible.

We have plenty of other things to do besides fiddling with Maestro that have higher priority such as separation and coordination. We'll take a look at it from time to time but things can change rapidly and catch us unawares. Changes rely on us noticing them - we don't get an alert to warn us.

As to why the gap, it could have been they managed to shorten up some of the aircraft ahead and compressed the sequence a bit and you were a bit slower than expected. It could have been a space left for a transiting medevac chopper. We don't just leave holes for the fun of it.

Do you know how this can happen?
 

The way traffic is sequenced in Aus is at the request of industry / airlines. They want aircraft absorbing all delay at cruise altitude, then staying on the STAR (because the FMC is more efficient than hand flying) all the way to touch down. If you're on the STAR all the way to touchdown how else can the sequence be organised. Speed up slow down. We all know you hate it, but the airline loves it. Sometimes I wonder why we bother because it's much more difficult than say sequencing like Heathrow. Just let em all cruise into the low level holding stacks, issue them standard speeds, then vector them onto final. So much easier than locking a dynamic sequence in at 200nm (40mins from now) when so much will happen between now and then. Especially if there is a bit of weather around, not just at the airport but enroute. While you're up there dodging cumulus the sequence is going to **** cause no one is achieving their RTA.

You being inside Aus airspace for 7 hours has nothing to do with it. You could be given a flow time then but it would most certainly be wrong. We can even see you on maestro well beyond 200nm but maestro can't see the aircraft that will beat you to the airport but haven't taken off yet. How do you flow a sequence with aircraft that aren't airborne yet? 200nm is just a number that seems to work best. In some circumstances when the traffic mix is right I've seen the sequence locked in at 350nm.

In a perfect world all this is great. You get your RTA in enough time to slow down and achieve it, descend at 250kts via the star all the way to touch down and everyone flows in like a zipper landing a perfect 4nm trail (for mixed mode) over the threshold. Very rarely is it a perfect world. But get used to it, Nextgen and Sesar are both based on the Aus ATC system. (Adjust speed to cross....)

Had the same thing happened to you at Heathrow, you would have stayed at your normal speed, done a lap of the holding pattern, probably two (10mins) at 5000', vectored onto final, then came here and told us how good Heathrow ATC (don't get me wrong it is very good).

Charlie, I'm sure that ASA management tell controllers that the system is broken because airlines/ industry want it that way, just as airline managers tell us line drivers that "ASA is heavily unionised and controllers won't change their practices". The truth may be a little from column A and column B but the fact remains that a 10 minute delay at 200 miles or less (common example) is not "absorbing all delay at cruise altitude"; but rather losing time on descent which whilst doable, is a major pain in the @rse in terms of energy management and efficiency.

You ask "How do you flow a sequence with aircraft that aren't airborne yet"?
Given that most traffic into capital primary's are RPT with a known schedule; I'd ask why cant you?

I can't see why you're getting your knickers all bunched up over it Haughtney,
the oz controllers apply some pretty insanely tight separations as it is - specially with the MEL 27 departures and 16/34 arrivals.

It happens anywhere in the world if you arrive at rush hour at a capacity constrained airport, specially one that has a mix of light turboprops and super-heavies and the occasional medevac etc.

It's just all about how they prefer to present the bad news to you ... the aussies tell you at TOD to cross Arbey with a 10 minute delay, and the brits tell you at TOD to expect 2 laps of the Lambourne hold. Doesnt make a blind bit of difference really except you then have to tell them ok we need a delaying vector. Kind of silly way to do it, but that's aussies for ya

That's pretty naive, Joe. Do you really expect multiple RPT aircraft could/would stick to their schedule plus or minus a couple of minutes so the flow would work with no slowdowns or re-sequencing?

Losing time in straight lines is better, fuel burn wise, than holding patterns. Nicer for the pax, too.

:ok: When I offer the choice of speeds and vectors or hold a large majority of pilots take the vectors.

Joe, even if everyone pushes back on time how does that account for different runways for departure and arrival, winds and Haughtney picking up 30 minutes over his 13+ hours in the air? Not to mention multiple aircraft scheduled to arrive at the same time.

The point is a dozen aircraft can end up all trying to land within a few minutes so there will be delays just because of the variables not accounted for by scheduling.

Le Pingouin - I understand the variables involved, however, the system should be at least smart enough to know that aircrew cannot possibly lose 10 mins in 200 miles. Better to say "expect Approach time at X, or expect holding for x mins or say nothing and just radar vector.

Perth is locking in JULIM estimates and slowing ppl down with 400 NM to run. Is this more what you want?

And while you're at it could you give YMML arrivals their ARBEY time 400nm out too?

Better still 1000 nm out ask me my ARBEY estimate, it will be very close.

Rex, it's the controllers doing the asking. We aren't expecting you to do the impossible but are giving you the time and letting you work with your magic box to see what can achieved & going from there. Rather than some long spiel we just give the time and you come back with what you can achieve. I'll often add "let me know what you can achieve" if I think it's not possible on speed alone.

Personally if I think you can get it down to less than a pattern with speed I'll give you the time. I've seen some quite amazing time losses coming into ML from BN (into the wind I guess) when I was expecting a 4 or 5 min vector.

ACMS, an accurate estimate is great, but it won't make an iota of difference because it takes no account of all the aircraft who have yet to depart who will be getting there before you.

400NM out? The controller who will be fiddling with Maestro may very well not even be aware of you at that stage and is busy working the sequence and handling their other duties for the aircraft they already have. As a pilot are you thinking about your next leg rather than briefing for the arrival you're about to make? That's what you're asking for. It's not the way Maestro works.

The fact that you guys don't know about us from 400nm away says it all.:rolleyes:

We can lose time to make a fix time from a couple of thousand.;)

A factor not often discussed is the random flying habits of poorly trained or under confident pilots.

Several carriers I have worked for are full of pilots who happily ignore ATC speed requests and pretty much do what ever speed they like on descent and will throw the anchor out at whatever point intrudes on their comfort factor.

The steely eyed missile men of ye olden days driving the 727 at 300 knots until less than 20 miles are gone, now replaced by kids who would rather stick like glue to an inaccurate DES profile and let the speed drift back to 260 knots than actually maintain an appropriate speed and run the numbers in their head.

Run the numbers in their head? Not anymore, no one teaches it. Many pilots these days have no clue about where they should be speed/height/distance.

Start training pilots a little better and forcing some flying discipline and things may work out a little better for ATC

Rant over.

I'm looking after a large chunk of airspace with maybe 20 aircraft to consider. Separation is the priority. I'll look at sequencing when I can, that's what it boils down to. My attention is quite necessarily focused on my airspace and immediate surrounds, not looking for aircraft to sequence a couple of hundred miles away.

You seriously can't be that dim?

TAAATS knows about you the moment you depart a foreign country. If you want to slow down on departure from that foreign country just in case you might get a delay, fill your boots.

That would be easier to swallow if we didn't have schedules and slot times, and if we weren't sitting at the gate watching a clock wind down as part of a Ground Delay Program. If I were to push back outside -5/+10 of my COBT then my friendly controller would remind me that I'm non compliant and can expect up to 60 holding. If I am compliant, then I can expect the same holding/last minute slow down/now quick speed up, as before the implementation of ground delay programs.

It's simply not acceptable to be tracked from one side of the country to the other, with a slot time, and COBT compliant to then be treated as a shock/ surprise at 200 miles. As airline Pilots, we work hard to be fuel efficient, only to then throw that efficiency out the window with a ridiculously inefficient descent.

In my neck of the woods, the GDPs have resulted a big reduction in holding.

Porter, me dim?:hmm:
Have you heard of SEMAC?:confused:

I was given a plan on a 8+ hour flight the other day giving me a range of times to be at Rivet. As we were fast it allowed for a 7 minute delay at the gate if I wished.:zzz:

This is reality now! :ooh:

While not taking the delay at the gate we did fly at a speed to get us to Rivet to the minute.:ok:

Of course then we got holding.:ugh:

We can do it, as requested, can you?