METRON ML
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FFS, what is it with you people? Do you think I sit here on the edge of my seat in angst with the problems of the world on my shoulders? Who's complicating it? Read the posts brah............
But you obviously know it all brother and have never been late out of the pattern 
blissfully ignorant of course because the controller is just getting on with it, (gees, why is he speeding me up and cancelling speed?) you're the expert and I bow to your FMS prowess...............hail lookleft
blissfully ignorant of course because the controller is just getting on with it, (gees, why is he speeding me up and cancelling speed?) you're the expert and I bow to your FMS prowess...............hail lookleft
Based on the above, you make far too many assumptions 
might pay to read what is actually written not make judgements on who you think I am as a pilot or person
might pay to read what is actually written not make judgements on who you think I am as a pilot or person
Most controllers find they can't just pass fix crossing time restictions and expect the aircraft to remain separated
As I see it, there needs to be a better understanding of what is necessary (need to cruise fast?) verses what will make things work when there are other aircraft close-by trying to also make the FF times.
Watching with interest.... JR, what about pistons who can't just slow down or speed up with ease. Whose flap and gear speed are sometimes quite lower than cruise. Whose fms is the cr2. Who's engines are susceptible to shock cooling. Give them a time of crossing etc and it can be a delicate ballet of slowly slowing the plane to putting flap down to oh crap now I lost 10 kias more than was asked... Etc Etc. Do you guys have a soft spot for them knowing that asking a turbo charged piston to maintain min speed to suddenly go to max or even at what point are you calculating the same aircraft to maintain max to the field...given the fact the engines need time to cool when reducing power and the "taps" just can't be closed on short final.
Honest question.
Honest question.
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As somebody pointed out earlier, a system like the Metron one is not designed to eliminate airborne delay/holding, especially if CTOT tolerance of that magnitude is permitted.
It is really more of a pre-tactical flow management tool to adjust the taps to stop the bath from overflowing in a capacity constrained situation (ie the plug hole is partially blocked!)
The objective is to still have some water in the bath (ie delay/minimal holding )to keep pressure on the system, otherwise you end up with the "go fast, track direct" situation.
Predicting the airport acceptance rate several hours ahead and adjusting those taps to the right rate, is the tricky bit.
It is really more of a pre-tactical flow management tool to adjust the taps to stop the bath from overflowing in a capacity constrained situation (ie the plug hole is partially blocked!)
The objective is to still have some water in the bath (ie delay/minimal holding )to keep pressure on the system, otherwise you end up with the "go fast, track direct" situation.
Predicting the airport acceptance rate several hours ahead and adjusting those taps to the right rate, is the tricky bit.
Last edited by bekolblockage; 5th Mar 2014 at 02:57.
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cwc, you need to take your performance characteristics into account when you are issued with these times. If it's something you can't achieve, tell the controller, they will vector for time loss rather than you having to slow down in a straight line. None of the instructions override your responsibility to conduct the flight safely. If you can't do something either operationally or safety related tell the controller. Controllers are taught in the college to expect these sort of replies.
What Wally said in one of his previous posts rings a bell. He manually calculates his top of descent even though he has an FMC. Do you have rules of thumb that take into account what you can and can't do with regards to engine management?
What Wally said in one of his previous posts rings a bell. He manually calculates his top of descent even though he has an FMC. Do you have rules of thumb that take into account what you can and can't do with regards to engine management?
Jack,
Thanks for taking the time to reply to this thread digression which I started a few pages back. We are all on the same team and trying to get the job done. It's disappointing that there's a lot of angst shown here towards ATC. We are all guilty of it in the heat of the moment but most of us accept that there's a big picture (but I do wonder if the picture couldn't be repainted with some better procedures).
I asked why the speed up after holding situation rears its head frequently (usually into ML) and I have a good answer from you.
I have heard it said over the years that there's a +/- 60 second buffer at "Cross XXXX at time YY". This "culture" no doubt compounds your problems when it's interpreted as a latitude in which to be good enough.
Also, I can't help wondering whether companies re-inventing approach profiles for the Airbus are half the problem, and the cause of half the cluster**** with times and the variety of speeds within the approach sector, which forced the speed restrictions of 12 months ago The Airbus does a pretty good job of sorting out a profile to the top of the OM when left to get to the DECEL point when and where it wants to (even via an RTA).
Up to about a year ago more than one Approach controller was heard to remark after best speed requests (to one company's aircraft not bound by these lowest common denominator speeds) something along the lines of "Never seen one do that before".
I was going to start comparing you favourably to Darwin (which I know is not you mob) but any mention of Darwin is probably best left to another thread....
Thanks for taking the time to reply to this thread digression which I started a few pages back. We are all on the same team and trying to get the job done. It's disappointing that there's a lot of angst shown here towards ATC. We are all guilty of it in the heat of the moment but most of us accept that there's a big picture (but I do wonder if the picture couldn't be repainted with some better procedures).
I asked why the speed up after holding situation rears its head frequently (usually into ML) and I have a good answer from you.
I have heard it said over the years that there's a +/- 60 second buffer at "Cross XXXX at time YY". This "culture" no doubt compounds your problems when it's interpreted as a latitude in which to be good enough.
Also, I can't help wondering whether companies re-inventing approach profiles for the Airbus are half the problem, and the cause of half the cluster**** with times and the variety of speeds within the approach sector, which forced the speed restrictions of 12 months ago The Airbus does a pretty good job of sorting out a profile to the top of the OM when left to get to the DECEL point when and where it wants to (even via an RTA).
Up to about a year ago more than one Approach controller was heard to remark after best speed requests (to one company's aircraft not bound by these lowest common denominator speeds) something along the lines of "Never seen one do that before".
I was going to start comparing you favourably to Darwin (which I know is not you mob) but any mention of Darwin is probably best left to another thread....
Last edited by compressor stall; 5th Mar 2014 at 03:52.
I've flown both and neither are all that hot when it comes to programmed holding times.
To be honest, now whenever I hold in the 737, the time the FMC indicates over the target is something I've always noted but not really followed. Like everything it has its limitations.
A piece of paper, a pen, a clock and some adjustments for wind, more often than not, see me there very close too, if not, right on the instructed time.
Higher winds, for my feeble mind, make it a little more difficult but you can still do a fairly reasonable job...
To be honest, now whenever I hold in the 737, the time the FMC indicates over the target is something I've always noted but not really followed. Like everything it has its limitations.
A piece of paper, a pen, a clock and some adjustments for wind, more often than not, see me there very close too, if not, right on the instructed time.
Higher winds, for my feeble mind, make it a little more difficult but you can still do a fairly reasonable job...
To be honest, now whenever I hold in the 737, the time the FMC indicates over the target is something I've always noted but not really followed. Like everything it has its limitations.
A piece of paper, a pen, a clock and some adjustments for wind, more often than not, see me there very close too, if not, right on the instructed time.
Higher winds, for my feeble mind, make it a little more difficult but you can still do a fairly reasonable job...
A piece of paper, a pen, a clock and some adjustments for wind, more often than not, see me there very close too, if not, right on the instructed time.
Higher winds, for my feeble mind, make it a little more difficult but you can still do a fairly reasonable job...
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A piece of paper, a pen, a clock and some adjustments for wind, more often than not, see me there very close too, if not, right on the instructed time
Unfortunately there is an increasing % of "Children of the Magenta" on both sides of the screen now.
Automation is great in many circumstances but you need to know when to step down a level.
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We are all on the same team and trying to get the job done. It's disappointing that there's a lot of angst shown here towards ATC.
We are all guilty of it in the heat of the moment but most of us accept that there's a big picture (but I do wonder if the picture couldn't be repainted with some better procedures).
The picture could always be re-painted but unfortunately you and I aren't listened to when these things are designed.
I asked why the speed up after holding situation rears its head frequently (usually into ML) and I have a good answer from you. I have heard it said over the years that there's a +/- 60 second buffer at "Cross XXXX at time YY". This "culture" no doubt compounds your problems when it's interpreted as a latitude in which to be good enough.
Also, I can't help wondering whether companies re-inventing approach profiles for the Airbus are half the problem, and the cause of half the cluster**** with times and the variety of speeds within the approach sector, which forced the speed restrictions of 12 months ago The Airbus does a pretty good job of sorting out a profile to the top of the OM when left to get to the DECEL point when and where it wants to (even via an RTA).
Up to about a year ago more than one Approach controller was heard to remark after best speed requests (to aircraft not bound by these lowest common denominator speeds) something along the lines of "Never seen one do that before".
I was going to start comparing you favourably to Darwin (which I know is not you mob) but any mention of Darwin is probably best left to another thread....
I know that if you came in and spent a full shift plugged in with a flow or approach controller you'd go 'ahhhhhhhh, that's why'
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A piece of paper, a pen, a clock and some adjustments for wind, more often than not, see me there very close too, if not, right on the instructed time.
Higher winds, for my feeble mind, make it a little more difficult but you can still do a fairly reasonable job...
Higher winds, for my feeble mind, make it a little more difficult but you can still do a fairly reasonable job...
Back to the OP.
Not sure what AS paid for the system (a shed load I hear) but its not exactly rocket science.
Work out ETAs based on EOBT and Estimated Elapsed flight time, stick in an arrival constraint, say 20 per hour, assign slots at 3 minute intervals and work backwards minus the EET to a CTOT.
Worth millions??? Really?
Not sure what AS paid for the system (a shed load I hear) but its not exactly rocket science.
Work out ETAs based on EOBT and Estimated Elapsed flight time, stick in an arrival constraint, say 20 per hour, assign slots at 3 minute intervals and work backwards minus the EET to a CTOT.
Worth millions??? Really?
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Ranga,
The mighty 777 does what it says on the tin….we always cross the fix within 6 seconds…if able.
The earlier the better for us helps with planning and getting to where you need us.
PER has definitely improved inbound…getting airborne however is another issue, even getting a taxi clearance from the intl terminal to depart from 21 feels like mission impossible.
Out of interest do you guys have a speed you plan the 777 in descent? the 300ER doesn't like anything below 280kts…..300-310 is better
The mighty 777 does what it says on the tin….we always cross the fix within 6 seconds…if able.
The earlier the better for us helps with planning and getting to where you need us.
PER has definitely improved inbound…getting airborne however is another issue, even getting a taxi clearance from the intl terminal to depart from 21 feels like mission impossible.
Out of interest do you guys have a speed you plan the 777 in descent? the 300ER doesn't like anything below 280kts…..300-310 is better
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Haughtney,
I consider 'profile' for most heavies 300-320. If you get 280 its to finesse a time, if you are getting 250 above 10 it's essentially minimum into the hold (to help clear the pattern).
p.s as a rule of thumb, if you need to lose 1-4 mins you'll get a speed (or ff time), 4-6 mins you'll get a turn (and possibly 280k if youve been turned back in a tad early ;-) ), 6+ and you can probably expect to hold.
edit: I see what you did there, nice try!
I consider 'profile' for most heavies 300-320. If you get 280 its to finesse a time, if you are getting 250 above 10 it's essentially minimum into the hold (to help clear the pattern).
p.s as a rule of thumb, if you need to lose 1-4 mins you'll get a speed (or ff time), 4-6 mins you'll get a turn (and possibly 280k if youve been turned back in a tad early ;-) ), 6+ and you can probably expect to hold.
edit: I see what you did there, nice try!
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....or the rwy change from 27/34 LAHSO to 16 only..
You have to determine what rate those different modes equate to under different operating conditions and tell IT.