Author Topic: Holdings  (Read 9819 times)

Offline Jonathan_tcu

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Holdings
« on: September 22, 2005, 04:52:34 PM »
This is interesting.  Up here in northern Ontario, we always hear "Expect approach clearance time of..."  and I am just listening to Toronto Ctr issue holds over the Simco VOR and the new terminology is "Depart the hold at a time of..."  

Is this normal? lol



Offline Jonathan_tcu

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Holdings
« Reply #1 on: September 22, 2005, 04:56:00 PM »
I'm going to add to this.  I'm also hearing the term from a CZYZ ctr controller "There are meterings over the Simco VOR, I'll confirm a hold depart time momentarily" or somewhere within that.  Is this normal too?

Offline binky

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Holdings
« Reply #2 on: September 23, 2005, 01:08:33 AM »
Expect approach clearance is normally issued when an aircraft is holding at a location from where the aircraft will then commence the approach into the airport such as an NDB or some fix on the localizer.  The depart Simcoe times are times issued to the enroute controller by the flow control department to give to the aircraft in order to meter or regulate the flow of traffic into the terminal.

Offline Jonathan_tcu

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Simcoe ATC guy
« Reply #3 on: September 30, 2005, 10:22:53 PM »
I was listening to the controller between 5 and 5:50 (21-2150z) from Toronto Center who I used to listen to on the Peterborough freq 134.25, funny guy who sounds like he likes to have fun.    Last night, he sounded really stressfull with trying to delay as many aircraft as possible over the Simco VOR.  And he's on again tonight, just past 10 pm or 0200z.  He's just fun to listen to.

Offline KSYR-pjr

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Re: Holdings
« Reply #4 on: September 30, 2005, 11:50:07 PM »
Quote from: Jonathan_tcu
This is interesting.  Up here in northern Ontario, we always hear "Expect approach clearance time of..."  and I am just listening to Toronto Ctr issue holds over the Simco VOR and the new terminology is "Depart the hold at a time of..."  

Is this normal? lol


My understanding is that, at least in the US, an expect further clearance time is normally a best guess by the controller.   A departure out of the hold may or may not occur at the EFC time.  

For the controller there to know with certainty when an aircraft is going to depart a hold is new to me, too.

Offline dave

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Re: Holdings
« Reply #5 on: October 01, 2005, 08:14:45 AM »
Quote from: KSYR-pjr
Quote from: Jonathan_tcu
This is interesting.  Up here in northern Ontario, we always hear "Expect approach clearance time of..."  and I am just listening to Toronto Ctr issue holds over the Simco VOR and the new terminology is "Depart the hold at a time of..."  

Is this normal? lol


My understanding is that, at least in the US, an expect further clearance time is normally a best guess by the controller.   A departure out of the hold may or may not occur at the EFC time.  

For the controller there to know with certainty when an aircraft is going to depart a hold is new to me, too.


This is correct...EFC times are estimates based on a best guess by the controllers.  That best guess isn't just a shot in the dark, though.  It's based on coordination with the ATC facility downstream who needs the flow held up for a bit, for whatever reason.  Most busy ATC facilities have a traffic management position, manned by a person who has access to a lot of information sources and who has the tools to analyze the traffic and provide estimates on EFC times, etc.

The controllers don't want us holding any more than we do, so they regularly pull planes out of the hold whenever they get the OK from downstream.  An interesting thing about coming out of a hold is that you technically need to be recleared to your destination since your clearance limit in the hold was changed.  Your route didn't change at all, but your clearance limit did.  If you lost communications then the controller would expect you to continue on to your destination *via whatever route you were told to expect before you lost comms*, or via your filed route, at the EFC time.  An example of being cleared out of the hold is:

"United 1523, turn left, cleared direct Gardner, Gardner 3 arrival."

When the weather is bad, you will regularly hear aircraft holding on the way into Boston:  http://audio.liveatc.net:8012/zbw_test.m3u

-dave

Offline Lexxx

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Re: Holdings
« Reply #6 on: October 01, 2005, 08:42:36 AM »
Quote from: Jonathan_tcu
This is interesting.  Up here in northern Ontario, we always hear "Expect approach clearance time of..."  Is this normal? lol


Yes it's normal. In addition to the other comments here, the reason an aircraft is ALWAYS given an EFC time for a hold is to protect against a comm failure. Although rare these days, the controller will expect the aircraft to follow "loss of comm procedures" at the EFC time. For example, if they are holding on a facility (NDB lets say) with the intention of landing at that airport, the controller expects the aircraft to commence the IFR approach to the airport at the EFC time, and the airspace is sterilized until the situation is resolved.  EFC times should be updated by the controller before the expiry, and the pilot usually initiates a request for a new time as the old one approaches.

Offline KSYR-pjr

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Re: Holdings
« Reply #7 on: October 01, 2005, 09:07:25 AM »
Quote from: dave
This is correct...EFC times are estimates based on a best guess by the controllers.  That best guess isn't just a shot in the dark, though.  It's based on coordination with the ATC facility downstream who needs the flow held up for a bit, for whatever reason.  Most busy ATC facilities have a traffic management position, manned by a person who has access to a lot of information sources and who has the tools to analyze the traffic and provide estimates on EFC times, etc.


One of my favorite web-based aviation authors is Don Brown, an air traffic controller who works the north end of the Atlanta sector.  He writes monthly articles for Avweb.com.  Coincidentally, his most recent article is all about holds.

After reading the following quote from his article, I got the impression that EFC times *are* more of an educated guess, rather than a well planned coordination of several ATC facilities.  Tell me what you think:


------------------  start article quote -------------------------------

(A quote from Don Brown's Avweb Article, "Holding")

While we're here, let me say a few words about Expect Further Clearance times (EFCs). EFCs are just a guess. They always have been and they always will be. I personally issue EFCs from a pessimistic point of view: I don't ever expect the "best-case" scenario when I'm forced to hold. And it's a rare day I have to reissue a later EFC.

Many of the controllers (perhaps most) I know are more optimistic than I am when it comes to issuing EFCs. That's fine. Different strokes for different folks. It sure is a pain to go back through a stack of 10-12 airplanes and issue every single one of them a new EFC, though.

Still, whether optimistic or pessimistic, the controller is just guessing. Much will depend on the airplanes in front of you. Will they shoot the approach quickly or slowly? Will they land or miss the approach? There are just too many factors at work to be able to give a precise EFC. I know that when pilots are watching the fuel gauges drop, they want to start asking questions. You might pressure a controller into giving you an earlier EFC but all you're getting is still a guess.

------------------  end article quote -------------------------------

For the entire article, go here:  

http://www.avweb.com/news/columns/190503-1.html

Offline dave

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Holdings
« Reply #8 on: October 01, 2005, 10:20:49 AM »
I read Don's column from time to time and enjoy him immensely.  But like anything else, you need to be careful to not believe everything you hear or read (including from me, what do I know!), and more importantly to avoid thinking that what they do at ZTL applies everywhere, or works the same everywhere, even though often it does.  

Sometimes there's coordination, and sometimes there isn't.  The TRACON/Center relationship is strained in some areas, and they sometimes like to communicate as little as possible.  Other places are different.

But even though there is some level of coordination in some places, most often the EFC time is a guess.

-dave

Offline Jonathan_tcu

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Holdings
« Reply #9 on: October 01, 2005, 08:37:27 PM »
I know the min holding time for aircraft on approach to our airport is probably 12 minutes.  This, even in MVFR conditions, in the event that two aircraft are scheduled for arrival, between 1  and 5 minutes apart.   This, even after the pilots request to reduce their speed to a minimum.

Sometimes the Toronto controllers really sound stressed out and end up making SOME mistakes and correct themselves later on.