CTOT regulation codes

[TO MEMO]

Hi

While reading the CTOT message, one can read in the end the regulation cause. Last night mine was TA83. Does any one have a list with the meaning of this codes?

Thank you

cheers

[2quiet]

I believe TA83 is Radar failure/RTF failure at Destination airport
There is a decode list in the ATFM Users Manual. Hope this helps.

[FlightDetent]

ok, I found something ATFCM_Users_Manual_Edition_12_0_FINAL.pdf (http://www.cfmu.eurocontrol.int/cfmu/gallery/content/public/userdocs/docs/ATFCM_Users_Manual_Edition_12_0_FINAL.pdf) (page 37), where's more?

FD (the un-real)

[PPRuNe Radar]

The table of codes can be found in the ATFCM Users Manual above, Annex 8 Page 27.

The first letter is the delay cause, the second letter is the phase of flight (A= Arrival, E= En Route, D= Departure).

The numbers refer to cause, using IATA code numbers, which also appear in the table in the Annex. Airlines transmit these for their own purposes.

IATA Delay Codes (http://en.wikipedia.org/wiki/IATA_Delay_Codes)

TA 83 would be an equipment failure at the arrival airfield.

[FlightDetent]

The table of codes can be found in the ATFCM Users Manual above, Annex 8 Page 27. You have me lost, Radar, I cannot find the page you reference, would you provide an overall (from the .pdf I linked) page number?

Thanks, FD (the un-real)

[PPRuNe Radar]

Page 105 of 110. The index only seems to show up to Chapter 13 (Page 75), so I can see how it was confusing !!

[TO MEMO]

Thank you guys!

Found the decode table in AFTCM users manual. Thanks FD!

cheers

[FlightDetent]

Radar:That is some serious black magic sir, must be an €control thing. :)

ToM: What good is a book if you can't read it? We bow to Radar. Actually thank you for the idea, got the page printed by now. Hey, on the next page there even is the official phraseology. :ok:

[criss]

If you have access to it, the ANM message has the regulation explained.

[BOAC]

I know his has been posted before, but to save excessive searching can anyone provide an ICAO def of CTOT? Radar's pdf seems to equate CTOT with 'Slot' but I'm sure there is a difference, in particular any 'leeway' on the time.

[FlightDetent]

Whatever the regulatory framework, certainly CTOT stands for point in "TIME" and there's no bounadry around that. If local/regioal regs allow for certain non-precision adhering to CTOT it effectively transformes to a time-window for departure commonly referred to as a "slot" I think. I must admit I have never came across an ICAO paper on flow management systems, albeit that certainly is not my field of expertise, which lately have been hard landigs:mad:.

This does not really answer your Q, does it?

[bookworm]

ICAO's PANS-ATM simply delegates the details to the regions:

3.2.1.5 Detailed procedures governing the provision of
the ATFM measures, and service within a region or area
should be prescribed in a regional ATFM manual or handbook.

I think CTOT is a European regional concept, and thus the time window that goes with it (-5/+10 mins) is also a regional detail.

Whether the word "slot" in common usage refers to the CTOT or the window around it may also be a cultural thing.

[PPRuNe Radar]

For the pilot, the slot is the CTOT. In other words, you need to be at the end of the runway ready to go at the time you have been issued. You have no leeway whatsoever.

ATC however have a 15 minute window (-5/+10) in which they can arrange for your flight to depart, to allow for traffic situations which may prevent you getting airborne at the precise time of the CTOT.

The 15 minute window is for ATC's use only. Pilots shouldn't build it in when planning their departure since ATC might not be able to give any leeway. For example, you might ask for taxy 2 minutes after your CTOT, and there is a 5 minute taxy time to the departure runway. In your mind as a pilot you think there is a 3 minute 'window' in which you can easilly get airborne. But there is a queue of 5 aircraft already on their way to the hold with a 2 minute departure separation between each. You won't make your CTOT window in that case and so ATC should not give you start/taxy. Certain routes have some ability for further extensions to the 15 minute window, but this will be a local agreement and not known to aircrew. Again, ATC will use it at their discretion if the individual flight meets the criteria.

It is important that pilots ask for start/taxy on time, every time. If you can't make it, then speak to ATC early and see what else can be arranged to manouevre your slot time. I wouldn't place faith in getting use of the 15 minute window every time, and if you do miss your slot, then you can expect a lengthy wait (at least initially) when you go to the back of the slot queue.

[FlightDetent]

It is important that pilots ask for start/taxy on time, every time. [/QUOTE] That is exactly what we are unable to do due to various tug / bag / pax identification / check-in reasons. Yet we strive.
If you can't make it, then speak to ATC early and see what else can be arranged to manouevre your slot time. Not all AD ATC units are able to utilise the CHA_MAN procedures. We attempt, withold information, presume and try. There is one strict ctoT with a small playground around. To hit it within limits allowed for our ATC overseers, for us the taxy time is certainly not based on pavement distance but time to line-up albeit the picture outside cockpit window does not reflect the overall situation (arrivals).

[BOAC]

For the pilot, the slot is the CTOT. - so you are saying there is no real difference? Why change the name? Is it just to confuse us all?:confused:

[bookworm]

- so you are saying there is no real difference? Why change the name? Is it just to confuse us all?

No, PPRuNe Radar is just making the point that the tolerance is not intended to be used at the the discretion of the pilot in calling for start/taxi.

"Slot" is a vague term. With a CTOT of 1810

* some say "the slot is 1805 to 1820" (probably the most grammatically sound usage)
* some say "the slot time is 1810"
* some say "the slot time is 1805" (earliest possible t/o time)
* some say "the slot time is 1820" (latest possible t/o time)
etc.

CFMU introduced the term CTOT so there would be no ambiguity as to what is meant.

[FlightDetent]

B_W & BOAC: Gentlemen, just look at the document offered above, page 107 for applicable RTF. Calculated Take-Off Time (CTOT) delivery resulting from a Slot allocation Message (SAM). (The CTOT shall be communicated to the pilot on first contact with ATC). : " SLOT (time) "
B_W: In the last five years over Europe(= my entire career :ooh:) I have never heard ATCOs miscommunicate the term as you indicate; perhaps "earliest airborne", "ctot at", "slots starts at", "latest airborne", but never ambiguous. CFMU in fact never introduced the term "CTOT" to R/T

The PPRuNe engine offers several suprisingly useful threads at the bottom of the page.
http://www.pprune.org/forums/showthread.php?t=307126
http://www.pprune.org/forums/showthread.php?t=275386
http://www.pprune.org/forums/showthread.php?t=154697
http://www.pprune.org/forums/showthread.php?t=15173

[criss]

Exactly as Flight Detent says. Sometimes we do say "your earliest departure time is" or "your latest departure time is" depending whether the CTOT is far away or shortly expiring, or if the crew is from outside Europe and does not exactly understand the concept. But I would never say "slot 1805" if the CTOT is 1810.

[PPRuNe Radar]

Not all AD ATC units are able to utilise the CHA_MAN procedures.

All ATC units should have a contact means with their own local or regional Flow Management Position, who can make the request on their behalf. In the UK for example, each ACC has a dedicated FMP with access to the CFMU both electronically and by telephone.

- so you are saying there is no real difference? Why change the name? Is it just to confuse us all?

As per the ATFM Manual, controllers will use the phraseology 'SLOT' when discussing it over the RTF. They are in fact referring to the CTOT. When discussing CTOTs over the phone, I've always used (and heard) the term CTOT. The 2 terms are interchangeable but mean the same thing. One is for radio use, the other for all other communications and procedures. As to why that is the case, Eurocontrol would have to provide the answer.

[BOAC]

Thanks FD and criss for saving my search fingers! As PPR confirms, they are indeed the same thing, and, Bookworm - I have never experienced the confused R/T you portray.

The confusion arises when cleverclogs ATC personage uses 'CTOT' on the R/T! They obviously need to read PPR's ATFM Manual.:mad:

[bookworm]

B_W: In the last five years over Europe(= my entire career ) I have never heard ATCOs miscommunicate the term as you indicate; perhaps "earliest airborne", "ctot at", "slots starts at", "latest airborne", but never ambiguous. CFMU in fact never introduced the term "CTOT" to R/T

I never suggested that it did. This is the first post in which you've mentioned RT phraseology. The word "slot" for ATFM purposes was around long before CFMU and the IFPS existed and was used ambiguously in, as I said, common usage.

To expand on that a little, if you read section 4.3 of the ATFCM Users Manual, you'll see that the word slot is used not just in the sense of CTOT, but also to mean "a reservation to fly through a particular piece of airspace at a particular time".

When CASA receives new flight data, it pre-allocates the slot as close to the requested
Estimated Time Over (ETO) the restricted location as is available:
a) If that slot is free, it is assigned to the flight, which thus suffers no delay.
b) If that slot is already pre-allocated to a flight which is planned to overfly the restricted
location after the new flight then the latter takes the slot.

To compound the ambiguity, the manual makes two references to "slot time". E.g.

SMM : SLOT MISSED MESSAGE
This message is originated by an AO when a slot time given in the SAM cannot
be achieved but where a new EOBT cannot be supplied.

If the word "slot" means "CTOT", what does "slot time" mean?

The problem with the word "slot" is semantic. It's used in a lot of different contexts in everyday usage: slots generally have widths. By contrast, "Calculated Take Off Time" is unambiguous. I'm not advocating the use of "CTOT" on RT, I'm just pointing out why a different label is useful and necessary in a broader context.