Sending REA-messages to CFMU
 

1. Is the EOBT time entered in the message meant to be the original, planned departure time of the flight or a new one estimated by the controller, based on the fact that the plane is ready for departure right away?

2. Is sending REA after the original EOBT complete waste of time, as the system has already given a CTOT based on that time?

3. Which of the following fields are mandatory? I've heard someone saying that for example EOBD is not necessary... True?

TITLE REA
ARCID <callsign>
ADEP <departure airport>
ADES <destination airport>
EOBD <date>
EOBT <time>
MINLINEUP <time>

From an ops point of view:

The EOBT are the original.
lots of time (almost always) our crew ask for a REA after the EOBT. Sometimes it work sometimes it doesn't so I don' t think that it is waste of time.

Ladies and Gentlemen

A REA may be sent between EOBT minus 30 Mins and CTOT of the flight.
When the REA is filed before the EOBT, the flight is considered as having a new EOBT at this filing time and the Minlineup as the revised taxi time.

To keep track of the difference between the filed off block time and the effective one in ETFMS all subsequent ATFCM messages include the field IOBT (IOBT= latest EOBT filed before the REA was sent)

That is straight from the book and I can tell you that it is THE best way to get an improvement if you are within the above mentioned parameters and have only one regulation. More than one reg then give us a call.

If you don't get improved its cos there ain't any room not because we are bloody-minded.
Prospero

L+G
Having re-read the original post I realised that my first answer didn\'t quite address the question. Here goes with a better attempt:

It\'s the new one.

No it\'s the best way (See my original reply)

As far as I am aware they are all mandatory. We often have two callsigns in the system with different EOBD\'s due to RPL\'s

I hope that helps if not give the CFMU a call. We really are lovely people ;)

Scenario, which happened last week.
Aircraft has EOBT AND Flight planned dep time of 0730.
Due to large delays at destination, CTOT comes through of 1215.
To keep the flight plan updated and within tolerance of HCS, the Handling agent / company update the planned ETD to 1200.
Three minutes later an CTOT is issued of 1510 !!!!!

By doing what is required in updating a flight-planned ETD, they attracted a further 2hrs and 55min delay. We checked with TMFMP and they said that if they had left the ETD alone then the original CTOT would have remained unchanged. However if they had done that then the flight plan would have dropped out of HCS!

The two do not appear to be working in harmony?

Comments anyone - confused:uhoh:

A certain operator where I work had a 3 hour delay into Dublin, so as I was sorting out a ready message another strip popped out........and then another! Their Ops thought it would be a good idea to file another 2 flight plans with slight differences in callsign in the hope that one of them wouldn't get a slot! Needless to say the London Supervisor was less than impressed!! :ugh:

@ Adola69

I think that you should have to talk with your :mad: handling agent.....

Adola69
This is a common misconception. If you are delayed by a CTOT you do not need to update your FPL unless you cannot make the CTOT. In that case you should send a DLA message. When your handling agent updated your EOBT the ETFMS took that as a delay and pushed into the next available slot, in this case at the end of the queue.

I can't remember the requirements for HCS but as far as I am aware if a flight is regulated it is taken care of by the CTOT as above. If not regulated then normal ICAO update rules apply.

Its all in our manual available from all good bookshops and the website.

Best Regards
PRospero;)

prospero- does that mean then that filing a Rea AFTER the eobt, say in the case of large CTOT delay will have no effect? You will already be trying to bring the CTOT forward as best as possible?

Evil-J
The idea behind an REA is that ATC can tell us exactly when an aircraft is actually ready to taxi and can be airborne in a very short time. It is there to help ATC with sequencing as much as anything.
That is why only the tower can send an REA and they can specify the taxi time.

Sending a REA within the parameters stated mentioned in the previous reply is the best way to get an improvement.

The REA will work best if there is only one regulation as that gives the computer the best chance of finding an improvement. It is all done by the computer as opposed to a help desk call where we use our "skill and judgement" (!) to move flights forward or back.
Hope this helps
Prospero

Here are a few more questions to clarify things. A following message arrived today:

-TITLE SAM
-ARCID <callsign>
-IFPLID AA51782718
-ADEP <xxxx>
-ADES <xxxx>
-EOBD 050928
-EOBT 1115
-CTOT 1124
-REGUL <xxxxxxx>
-TAXITIME 0005
-REGCAUSE GA 87

When the aircraft requested start-up and REA, I sent the following message at exactly 11:11:45(sec):

-TITLE REA
-ARCID <callsign>
-ADEP <xxxx>
-ADES <xxxx>
-EOBD 050928
-EOBT 1112
-MINLINEUP 0003

On the next minute we got an improvement as follows:

-TITLE SRM
-ARCID <callsign>
-IFPLID AA51782718
-ADEP <xxxx>
-ADES <xxxx>
-EOBD 050928
-EOBT 1111
-IOBT 1115
-NEWCTOT 1117
-REGUL <xxxxxxx>
-TAXITIME 0005
-REGCAUSE GA 87

Later I had another case with exactly similar results.

Ok prospero, you said:

It truly seemed as the new EOBT was the filing time of the REA, and NOT the new EOBT time entered by me. Also the taxitime did not get any revision (is 0005 a minimum?) Under these circumstances, why on earth do we have to enter an EOBT and not just simply send a REA with nothing more than ARCID, ADEP and ADES. If she is ready right now, then she is! Also a colleague told he regularly removes the entire EOBD -line and receives SRM:s normally. The need for it seems a bit unclear, because how could anyone assume a flight planned for tomorrow (in case of RPL) would be ready for departure NOW :confused: :D .

My common sense says that the EOBT should be the original and planned EOBT so that the CFMU's state-of-the-art computer would detect the correct flight plan. There could always be the same callsign flying the same route many times a day!

What difference does it ultimately make? You are already trying to improve the CTOT (or not?). I don't get the point...

another problem with REA
 

"It is not possible to amend (via CHG or DLA) the EOBT to an earlier time than the EOBT given in the flight plan however, if a flight is ready to go off blocks earlier than the current EOBT, then there are two options available:
©¤ The AO may ask the local ATC Unit (TWR) or the FMP to send a Ready (REA) message. In this case, the flight is considered as "ready to depart" from the filing time of the REA message.
©¤ The AO may contact Central Flow Help Desk who have the possibility to input an earlier EOBT into the TACT system (max ¨C30 minutes). Each case is treated on its merits and may be refused if it is considered that "abuse" is involved.".

My question (or better: pray :) : Is there any chance to make ATC staffs aware that when a crew is asking to leave earlier (providing not regulated by a CTOT) by using a REA, they are entitled to do so?
As far as I'm concerned, in Italy, Greece and Spain is very very hard to have such option available, since controllers standard reply is "ask yr ops to amend the eobt or the fpl"...

Cheers

Can anyone confirm that as an Ops Man could l put in a REA message from a sita terminal or is it only ATC that can do this, there is an option on the CFMU to send an RFI message but never seems to do too much!

ATC only
 

REA can be sent by ATC only. Ops can only send RFI (REA has anyway priority on RFI, then if a fpl shows a REA status, is not accepting any further RFI).

The ability for an OPR to send an REA was specifically removed as the system was being abused.

Airlines were sending REA's and receiving slot improvements when they were in fact NOT READY to taxi. This caused higher delays and a number of slots to go unused.

REA: mandatory fields
 

Original question: True, according to CFMU 10 release notes
http://www.mxp-users.com/cfmu_release_notes_10v2.pdf
page 32.

prospero,
The CTOT has no effect on the HCS "P" time [Proposed departure time]. That has to be done manually [at Manch, dunno about elsewhere]
The SSR drops after 90 mins, and I think that it's 4 hour for the Flight Plan to fall out
watp,iktch

Bloody hell Chiglet it only took you a year to answer my query. Talk about delay, you should work here...
Prospero
PS If you think hard you may remember me, I sat next to you for a few years in Manch tower....

'sNot me. It's that huv character. HE resurected this thread :ok:
How ya doin' mate?
watp,iktch

Apart from the technicalities of the flow system, am I the only one who thinks that, faced with:

-EOBT 1115
-CTOT 1124
-REGUL <xxxxxxx>
-TAXITIME 0005

filing a ready message is a waste of time and ties up the system unnecessarily? What with taxi times and slot tolerances, that's an on-time departure!

CTOT
 

Hi there,

ATC and Pilots have some problems with CTOT everywhere I think. REA is sent only when you have a CTOT given by CFMU. REA is not applicable for earlier dep what some pilots want. Normaly, FPL is available to ATC 30 min prior EOBT and if TWR or APP ask ACC for a clearance, it will be given without any problem. It means, you guys-pilots, if you want to depart earlier than EOBT, be polite and ask ATC for sturt up and taxi within 30 min of your EOBT. REA is sent to TWR and AO and sometimes is very late. Normaly, when there is any CTOT available earlier than you have, it will be given to you as an improvement or proposal for a new CTOT. It is on you to accept. Sometimes, CTOT is revised and is given even worse than previous one, why, due to some new regulations established or the previous one is more restricted. We know that you are in a hurry sometimes and we do our best to help you pilots. When you have a CTOT given, you have to depert within tolerance -5/+10 min of your CTOT. Sometimes we do for example +12, it is on our responsibility, just to help you not to ask for the new one if you are late by 2 min.

I wish you a nice flight with no CTOTs.