BNE ATC Holding

[Jack Ranga]

Angle of Attack,

When I was doing arrivals () one minute early is taking the p!ss, 30 seconds is perfect (approach can tweak your speed if they need to lose that thirty seconds) but late, even thirty seconds is a complete pain in the arse. It's very easy to lose time (vector, speed control) it's extremely hard, as you'd know, to make up time at that phase of flight.

[Roger Sir]

If only real world pilots and controllers could regain charge maybe some practical, useful and efficient solutions might prevail.

Tell him he`s dreamin!

Recent events at ASA have seen the "experts" in Canberra stuff up ALOFT. Until there is a distinct change in attitude from Canberra, and the field controllers are consulted, then sadly i see no change.

[Capn Bloggs]

I suppose you guys realise some FMS eg Honeywell don't display Est Time Over waypoints to the second?



Even when the FF is the next waypoint, we only get a 6 sec accuracy display.


Generally, it's almost too late to do anything about it (unless you're early, in which case a drastic slowdown can fix it, as Jack mentioned).

Also, what actually is THE time? Say the FF time 0845. The norm when talking about a number is to round it. So 0845 is 0844:30 to 0845:30. So when the box says 0845, it could be 0845:01 or 0845:59. There is no way of knowing what it is without some detailed experimenting, fiddling the FMS speed, to find the exact 0844>0845 changeover point.

If only real world pilots and controllers could regain charge maybe some practical, useful and efficient solutions might prevail.

What is required is a complete change of mindset of the operators/pilots. Make your slot or else. That's the way Europe operates, and the way we'll have to. If you're early on your FF time, you're screwing somebody else.

[amberale]

Not always possible Cap'n.

Some FMSs are better than others in this detail.

We regularly give the little busses a FF only to be told that they can't get there until a later time.
They then turn up early.

Not the pilot's fault but the data the aircrafts FMS is based on.

The main problem with most of our airport delays is, as Pdubby says, the runways or lack of them.

AA

[flightfocus]

This is without doubt the best thread I have ever seen on PPRUNE.

Everyone sharing information, staying on topic, no F*&*^#ts slagging each other, no pissing contest's and an informative read.

Well done all.

[VH-Cheer Up]

Sounds like resolution of the FMS time display is one issue - but how are FMS synchronised? If from a satellite then OK, but if not, my 0845+-:30 could be the next person's 0846 or 0844, +- recurring to infinity.

Whose clock is the real clock?

[Jack Ranga]

We regularly give the little busses a FF only to be told that they can't get there until a later time.

Never trust an airbus, in particular an A320. They will burn you every time.........every time

[havick]

P-Dubby, quick question for you.

ERSA states that aircraft with a slot time can expect a maximum 10min airborne delay, except GA aircraft which will be allocated a delay IAW traffic priorities.

so does this mean that if you're not RPT etc that even with a slot time to expect a delay (realistically) greater than 10 mins (assuming you make your slot time etc)?

the ERSA then goes on to say ground delays will be implemented if airborne delays exceed 60 mins

I can't see this actually happening for any GA arrivals, (even with a slot time).


After re-reading all that it would seem that for a GA aircraft arrival during a busy period, a slot time really holds no weight anyway. so with this in mind, how much fuel should we realistically need to carry if we really need to get into brisban and diverting to AF is not an option due to operational req's?

It's all very unclear as to how much fuel you really need due to holding.

[havick]

P-Dubby.

THanks for your informative response. At least we both agree that the ERSA is very ambiguous, and doesn't really offer much with regard to expected delays (read flight planning - fuel etc).

Ideally we would plan to arrive outside of peak periods (the few times we do have to arrive) and fingers crossed it wouldn't require an ILS and then break off for the GA apron (helicopter).

Sometimes though we have to meet a corporate jet to pick someone up, so at least now we can either plan to get there considerably earlier (outside of peak times - aircraft availability might prevent this), or carry the go-juice and just let the pax on the ground know to expect delays.

From an operator level, I really don't mind at all extended periods of holding (helicopters in IFR arrival - bad weather), it would be nice to know a worst case scenario in order to stack on the fuel otherwise organise alternative arrangements in advance and pass it on to the client if the fuel tanks aren't big enough.

cheers, havick

[havick]

it's rare, generally only when the weather requires it to get visual.. otherwise it would just be the typical sighting jet traffic and manouvering as req'd for the GA apron.

All of the above only really applies when it's crap weather requiring an instrument approach to get in. essentially making a helo (with more limiting fuel tanks) an aeroplane until you're visual.

[Capn Bloggs]

Sounds like resolution of the FMS time display is one issue - but how are FMS synchronised?

Most modern ones are GPS updated.

[le Pingouin]

As is TAAATS.

[Angle of Attack]

When I was doing arrivals () one minute early is taking the p!ss, 30 seconds is perfect (approach can tweak your speed if they need to lose that thirty seconds) but late, even thirty seconds is a complete pain in the arse. It's very easy to lose time (vector, speed control) it's extremely hard, as you'd know, to make up time at that phase of flight.

Jack Ranga,
Thanks for that, I always suspected slightly early is better than slightly late, as as you say its easier to lose than gain time in final stages of approach. I will now try and spread the word to some +-1min crew (but then when they stuff it and it blows out to 2 mins late just say OK well tell ATC we are gonna be late at around 5 mins to the fix... lol) and aim for the -30s to on time goal. Thanks

[amberale]

Havick I have often wondered about corporate jets flying private rather than charter.

If the company was set up with a seperate flying company section could you not operate the flying wing seperately and charge the corporate section for services?

This would then make you non scheduled RPT and equal priorities.

I don't know if there are other costs associated with this but if it means your corporate travellers get to their meetings on time it might be worth it.

I am sure a small restructure would be no problem for the accountants.

Just a thought.

AA

[havick]

Amberale... that's a good thought, but wouldn't quite work with the technicalities of this particular operation (I'd probably be crucified for publishing commercial in cofidence stuff publicly). Needless to say we can't tick the military box on a flight plan.

[Genisis Dreaming]

Havick,

With having 'clients' and not owners, doesn't this make you a charter operation and not GA. Hence, you should be able to plan N and not G. Same going if you're meeting a jet with 'clients' and not 'owners'?

My understanding was any charter operation was cat N, not G.

P-Dubby can you elaborate?

[havick]

Holding is never an issue when the weather allows visual approach as we just make an approach to the GA apron. It's when the weather is crap (seems to be the case every time I get tasked) that you need to punch an approach to get in, in which case a helicopter is no different to a fixed wing until visual.

Category type aside, if we know what delays to expect at least we can then forward plan accordingly. At the moment it's pretty unclear and the ERSA is fairly vague about it all.

** Edited - removed some company intricacies

[Dickcheese]

A little known fact is that around about the time we lost CROPS, the criteria from changing to Instrument Approaches (and thus more spacing) was altered. Whereas a cloud base of 2500 ft was the cut-off it was changed to 3000 ft for runway 19 and 3000 ft to the south or 4000 ft to the north for runway 01. Something to do with a visual point on the STAR.
I think this change was masked by the loss of CROPS but imo it hasn't helped with holding.

[max1]

Thanks for that, I always suspected slightly early is better than slightly late, as as you say its easier to lose than gain time in final stages of approach. I will now try and spread the word to some +-1min crew (but then when they stuff it and it blows out to 2 mins late just say OK well tell ATC we are gonna be late at around 5 mins to the fix... lol) and aim for the -30s to on time goal. Thanks

I hope this thread has been informative for pilots. But don't assume that you are helping by trying to be on the early side. Aim as close as possible to the time you have been given, always. ATC will then assess and massage you into the sequence based on what those in front of you have achieved. This has been discussed on Pprune before. Pilots don't have the full picture and sometimes neither does the arrivals ATC.
In a nutshell, MAESTRO ( flow computer) works on a Feeder Fix time ( a defined point somewhere on a 45nm circle from the aerodrome) , adds a distance to landing predicated on the duty runway and calculates a landing time. It continues to assess these landing times as aircraft progressively get closer to the field and eventually locks in a time. When delays are required it uses this calculated landing time and works out a sequence wherein delays are shared.
The FIRST TWO MINUTES OF DELAY are assigned to the Approach unit to absorb, above this then becomes the arrivals controllers responsibility. In this instance, aircraft may have a MAESTRO delay that the Arrivals controller DOES NOT KNOW ABOUT.
If the arrivals controller has all the aircraft in the sequence through their FF it is easy for them to work out that the sequence is A,B,C,D and E, and that MAESTRO is applyinga 2 minute delay for Approach to fix. Approach will be looking for around 10nm spacing and no huge speed difference at the Feeder Fix point.
MAESTRO may show that B and C can come across at the same time, C will actually be getting stretched out in Approaches airspace. Usually the sequence is a mix of aircraft from different FFs. Arrivals sectors have Maestro set up to show the required times that their aircraft are required to cross their Feeder Fix, Arrivals can access a Runway View that shows ALL landings and can see how their aircraft fit into the whole landing sequence but can't second guess how the Approach controller will achieve this , as the Arrivals controller does not have the full picture of what the Approach/Departures cell are doing.
With the example above, there may be no aircraft landing in the slot ahead of A, Approach's plan may be to shorten A and B up thereby negating the need to stretch C,D, and E.
X is slow departing due Y missing a high speed exit after landing causing A and B to now NOT being shortened up, C now needs to fly those extra 2 minutes causing D to need those 2 minutes, D's time at the FF was actually 0823.4 rounded down to 0823, D thought they were helping by being there at 0822. Controllers plan A is out the window. A and B to continue downwind, C onto a vector/ speed reduction , D is fair up Cs clacker big vector/ speed reduction for D.
D thinks "I got on Pprune asked the questions turned up a bit early at the Feeder Fix to help out like they asked and get stuffed around like this. This has got to the most incompetent bunch of ATCs in the world." This is ATC on a minute to minute basis. P.S. This is not aimed at AoA.
It's great that we get to have this dialogue here, but just aim at the time we give you and let us stuff you around from there. Cheers.

[max1]

Fair enough P-Dubby, it is the Bne ATC Holding thread.
Sydney is even more complex in that with dual runway ops MAESTRO will may have 3 aircraft for Rwy Left, Right, Left due through the FF all at the same time as the second aircraft will be getting its delay in the terminal area.
P-Dubby, in Brisbane, do you want them at the FF early/on time, on time, on time/late?