ATC

Dave S wrote:
Jim Logajan wrote:


The poster said these were ATC transmissions, not internal company
communications. Since ATC doesn't concern itself with weight, balance,
or any other flight performance factors, your explanation is almost
certainly wrong.

So if a flight was ready to push back,.. or number 2 or 3 for takeoff,
they wouldnt possibly decline a departure clearance or takeoff clearance
in the manner described?

The OP described two different transmissions - one from the ATC asking a
question and one presumably initiated by the aircraft. I'm still not sure
why ATC would ask or be interested in whether the aircraft has the sort of
numbers Jay mentions.

So you think Jay was almost certainly right and I am almost certainly
wrong? That is possible, but I'd like a bit of evidence that that is what
the alleged exchanges are all about.

Because we all know how people stick to exactly what the AIM and the
pilot controller glossary.. right?

Um, okay...

The use of "have numbers" is mentioned in AIM section 4-1-13:

Use of this phrase
means that the pilot has received wind, runway, and altimeter
information ONLY and the tower does not have to repeat this information.

If they didn't have the numbers, as referenced in this manner, ATC could
just GIVE em the numbers and clear em anyways.. because we all know that
"have numbers" doesnt subsstitute for "having information alpha" or
bravo or whatever..

Interesting analysis. I'll wait to see if those who have actual experience
with airlines see this thread and can shed light. Prior to the start of
this thread I already knew what I thought was the common meaning of "have
numbers" - which is even mentioned in the AIM, among other places. Are you
saying there is a different meaning in use? If so, is there a reference
that mentions it?

Jim Logajan wrote:


The OP described two different transmissions - one from the ATC asking a
question and one presumably initiated by the aircraft. I'm still not sure
why ATC would ask or be interested in whether the aircraft has the sort of
numbers Jay mentions.


I can think of one. The AC had previously refused a clearance because of
the lack of "the numbers." Though I tend to agree with you that in both
cases they were probably talking about ATIS,

On Mar 28, 1:09 pm, Jim Logajan wrote:

The OP described two different transmissions - one from the ATC asking a
question and one presumably initiated by the aircraft. I'm still not sure
why ATC would ask or be interested in whether the aircraft has the sort of
numbers Jay mentions.


The aircraft can't depart without that information. ATC does not want
to taxi aircraft that can't depart because they block other aircraft
from departing.



So you think Jay was almost certainly right and I am almost certainly
wrong? That is possible, but I'd like a bit of evidence that that is what
the alleged exchanges are all about.


What sort of evidence would satisfy you?

On 2008-03-28, Jim Logajan wrote:
The poster said these were ATC transmissions, not internal company
communications. Since ATC doesn't concern itself with weight, balance,
or any other flight performance factors, your explanation is almost
certainly wrong.

You haven't had an airline flight pause on the taxiway waiting for this
information? I have, as recently as last week.

ATC would indeed care if the aircraft wasn't ready to go yet because it
couldn't legally depart. For them to ask if the crew had "their numbers" yet
(note, not "the numbers") would make sense if, for example, they were going
to hold off obtaining IFR release from Departure until the flight was ready,
and the crew had advised them they weren't because they hadn't gotten that
information.
--
Jay Maynard, K5ZC http://www.conmicro.com
http://jmaynard.livejournal.com http://www.tronguy.net
Fairmont, MN (FRM) (Yes, that's me!)
AMD Zodiac CH601XLi N55ZC (ordered 17 March, delivery 2 June)

Jay Maynard wrote:
On 2008-03-28, Jim Logajan wrote:
The poster said these were ATC transmissions, not internal company
communications. Since ATC doesn't concern itself with weight,
balance, or any other flight performance factors, your explanation is
almost certainly wrong.

You haven't had an airline flight pause on the taxiway waiting for
this information? I have, as recently as last week.

ATC would indeed care if the aircraft wasn't ready to go yet because
it couldn't legally depart.

While you may be right, I'm having a difficult time understanding why ATC
would concern itself with something unrelated to traffic control - unless
the PIC first brought it up. In any case, I thought weight, balance, and
such "numbers" were strictly a PIC responsibility.

For them to ask if the crew had "their
numbers" yet (note, not "the numbers") would make sense if, for
example, they were going to hold off obtaining IFR release from
Departure until the flight was ready, and the crew had advised them
they weren't because they hadn't gotten that information.

Okay - it would make more sense (to me, anyway) only if it was the pilot
who first brought up not having their "numbers" as the reason they might
not be as ready as they claimed. I also assumed the more well known meaning
of "have numbers" was involved here.

Jim Logajan wrote:
Jay Maynard wrote:

On 2008-03-28, Mike Gilmour wrote:

Listening to Boston ATC at various times the Tower controller asks a
flight if they 'have got their numbers" (?) or a flight will say
they're not ready to proceed because they "don't have their numbers".
What does this mean as it doesnt translate here in the UK?

This refers to the flight performance data (primarily, weight and
balance) that the flight crew needs to enter into the flight
management system. The crew usually has that before they push back
from the gate, but occasionally the airline doesn't get it to them
until later. They can't take off without it, because they can't verify
that the aircraft is within its center of gravity range or that the
accelerate-stop distance is shorter than the available runway length.


The poster said these were ATC transmissions, not internal company
communications. Since ATC doesn't concern itself with weight, balance,
or any other flight performance factors, your explanation is almost
certainly wrong.
/snip/
Jim, the answer Jay gave is almost certainly *correct*. ATC absolutely
cares about weight & balance, if, said aircraft is number one for
takeoff, but unable to do so since they don't have the necessary data.
Now you've got the guy at the front of the line holding up the whole
airport! I've heard several heated exchanges take place in these
situations between ATC and the offending airliner. If a ground
controller knows that a departing flight doesn't yet have their
"numbers", he may taxi them via an alternate route, so as not to
obstruct the other departures.

As for the ATIS "numbers", this is typically verified when the flight
receives it's IFR clearance, so Ground Control can assume they already
have this information.

Happy Flying!
Scott Skylane

Scott Skylane wrote:
Jim Logajan wrote:
The poster said these were ATC transmissions, not internal company
communications. Since ATC doesn't concern itself with weight, balance,
or any other flight performance factors, your explanation is almost
certainly wrong.
/snip/
Jim, the answer Jay gave is almost certainly *correct*.

Okay - I sit corrected.

ATC absolutely cares about weight & balance, if, said aircraft is
number one for takeoff, but unable to do so since they don't have the
necessary data.

I see. But wouldn't it be more accurate to say ATC only cares that the
aircraft isn't ready and the specific reason in this case is common enough
that it has a colloquialism or slang term attached to it?

On 2008-03-28, Jim Logajan wrote:
Scott Skylane wrote:
ATC absolutely cares about weight & balance, if, said aircraft is
number one for takeoff, but unable to do so since they don't have the
necessary data.
I see. But wouldn't it be more accurate to say ATC only cares that the
aircraft isn't ready and the specific reason in this case is common enough
that it has a colloquialism or slang term attached to it?

That's not a bad way to put it. ATC cares about the delay, and an airliner
not getting the information it needs in time to taxi directly to the runway
and take off is one common cause for that delay.
--
Jay Maynard, K5ZC http://www.conmicro.com
http://jmaynard.livejournal.com http://www.tronguy.net
http://www.hercules-390.org (Yes, that's me!)
Buy Hercules stuff at http://www.cafepress.com/hercules-390

On Mar 28, 12:16 pm, Jim Logajan wrote:

The poster said these were ATC transmissions, not internal company
communications. Since ATC doesn't concern itself with weight, balance,
or any other flight performance factors, your explanation is almost
certainly wrong.

ATC does, however, need to know if the pilot has the current ATIS
(Automated Terminal Information Service) information: ceiling,
visibility, wind, altimeter setting, runway in use, and any special
airport information.


The KGRB ATIS includes a statement advising air carrier aircraft to
make sure they have their numbers before calling ready for taxi. It
was added because Northwest became notorious for taxiing without them
and blocking other departures while they waited for them.

On Mar 28, 5:16*pm, Jim Logajan wrote:
The poster said these were ATC transmissions, not internal company
communications.

Hi Folks

I'm the guy that dropped the pebble in the pond on this one.

I'm doing my UK PPL and listen to Live ATC feeds in 'background' when
doing tedious work at home. Due to UK law we can't get feeds from any
UK airfields so it's intersting to tune in and hear you guys waking up
across the pond.

It was a question I posed on the UK GA web site (www.ukga.com).

I was listening to Boston ATC and what I heard was a flight taxying
for departure telling the Tower that they needed more time because,
"We don't have our numbers", not "the numbers".

Later the Tower controller calls him back and ask him, "Have you got
your numbers" (not "the numbers") and advising the flight he'll have
to pull him over to let other flights through if he wasn't ready in a
jiffy.

Now there seems to be at least a couple of occasions where the time
delay between the flight first saying they weren't ready and their
still not being ready when the controller called them back was
significant, i.e to my way of thinking much longer than it would have
taken for the crew to tune to ATIS and get the lastest information.
Indeed why would they have pushed back without the ATIS?

My thought was that it must have something to do with the load figures
and the weight/balance calcs. And that the Tower didn't want the guy
to get to the head of the queue at the hold point and not be certain
he was ready to go.

So I think I'm with Jay on his explanation.

However it does show how confusing using shorthand phrases like 'the
numbers' can be!

Glad to know it's generated some stimulating debate!

Cheers

Ed