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2013-11-05 12:00 AM
A-1) The number of characters in the surveillance equipment and capabilities subset of Item 10 has been defined as a maximum of 20 characters. However other subsets in Item 10 have not had ‘maximum characters’ defined, nor had many of the other fields. Recognizing that a defined number of characters per field or sub field was valuable when coding software as it removed any need to make field capacity available that would never be used, the meeting sought clarification as to the different approach applied to different fields. The meeting also considered that agreeing on an Asia/Pacific requirement for number of characters per field or sub field would result in worthwhile standardisation and economies for States and should be pursued by the Task Force and adopted as a regional flight planning constraint.
(2) NormalClosedSSILVA
The limitation of 20 characters for the surveillance equipment and capabilities of Item 10 was considered appropriate taking into consideration the number of possible entries. For the navigation/communication equipment and capabilities, it was recommended not to establish a limit due to the number of possible combinations.  The creation of a regional “sub-specification”, while beneficial for intra-regional operations, may pose significant impact on inter-regional operations by raising both the complexity and potential for the establishment of regional standards that, in the aggregate, may exceed the overall message length limitations. Considering the above, it is recommended to keep the size of Item 10 for the NAV/COM with the capacity to inform the recipient of as many equipment and capabilities as possible, and to balance this with the message total length.
2013-11-05 12:00 AM
A-2) … the International Air Transport Association (IATA) raised concerns that the allocation of 16 characters to PBN/ in Item 18 may not be sufficient to adequately record the number of PBN approvals in some instances of long haul flights through a multitude of differing RNP airspaces. IATA would investigate this matter more fully and inform the next meeting of the outcomes.
(2) NormalClosedSSILVA
The maximum number of possible combinations is 28 characters. This is possible if one aircraft is capable of most PBN operations with some capabilities only provided by specific sensors. The new provisions cover a representative subset to support a long-haul flight. Typical capabilities will be covered by 16 characters. The intent of IATA to investigate further is noted.
2013-11-05 12:00 AM
A-3) The sequence of information in Item 18 has been defined, ensuring that the Item 18 information would be inserted in a specific and repeatable order. This was not the case in Item 10, for example, suggesting that Item 10 information could be inserted in any order. Recognising that a specific sequence of codes was more easily ‘read’ by automation equipment, the meeting sought clarification as to the different approach applied to different fields.
(2) NormalClosedSSILVA
Regarding the sequence of information in item 10, this was not amended, but if for automation purposes it is necessary to do it, it should follow the alphabetical order as presented in Doc 4444.

The order introduced in Item 18 was in recognition of the limits imposed by the AFTN, and duplicated in some existing ATC systems. The order is a priority order intended to ensure that if the message is truncated the likelihood would be that the lost data would be the least important.
2013-11-05 12:00 AM
A-4) In Item 7, the presentation of the Amendment indicated item b) occurring before item a), as shown below, rather than the traditional presentation whereby a) normally precedes b). The rationale for this was unclear and could bestow undue priority on the use of registration markings as the radiotelephony callsign for each flight. The meeting confirmed its strong preference for ‘flight number callsigns’ and agreed that in the Asia/Pacific implementation, use of the designator for the aircraft operating agency followed by the flight number would take precedence.
(2) NormalResolvedSSILVA
The comment is accepted and items 7 a) and b) will be reordered in the published amendment.
2013-11-05 12:00 AM
A-5) Item 10 requires the use of ‘N’ if no COM/NAV/approach aid equipment is carried, or ‘S’ if standard COM/NAV/approach aid equipment is carried. However the example given at the end of Item 10 does not include N or S, see below: Is there a number of characters limitation on this field that, when reached, results in dropping the first character – or should the S or N always be included?
Example: ADE3RV/HB2U2V2G1

(2) NormalClosedSSILVA
The S or N will always be used when they are required to inform the recipient of Standard or NO COM/NAV equipment. The example describes a specific situation where S or N do not apply. Regarding the limitation on the length of the Item, see A-1.
2013-11-05 12:00 AM
A-6) The changes contained in Appendix 3, Air Traffic Service Messages, now require that Item 18 (Other Information) must now be included in CHG, CNL, DLA, DEP and RQS messages. Although it appears this change is necessitated by the new allowance of FPL filing up to 120 hours in advance which requires inclusion of DOF/ in Item 18, the Amendment 1 to the PANS ATM has the effect of requiring that the entire Item 18 be routinely included in CHG, CNL, DLA, DEP and RQS messages. Item 18 is a very lengthy field, so the change has the consequence of vastly increasing the size of ATS messages being sent over AFTN networks and greatly increasing associated message storing and processing functions in ANSP systems which handle these messages.
 The example CHG message shown at paragraph includes a DOF/ change, but does not include other Item 18 information (see below), also suggesting that the intention is simply to transmit DOF/ changes in CHG, CNL, DLA, DEP and RQS messages, rather than the full Item 18 information.
 However, recognising that in automated systems the technique of completely overwriting a full field rather than amending a small portion of a field is commonly used, the meeting realised that it was possible that the new requirement to transmit the entire Item 18 in CHG, CNL, DLA, DEP and RQS messages was necessary. However, the Task Force would study whether adoption of a regional constraint that would result in DOF/ being the only Item 18 information included in CHG, CNL, DLA, DEP and RQS messages was at all feasible. The meeting considered that an urgent clarification was required in this case, as it could not identify any advantage to including full Item 18 data and either the routine transmission of bulky data or adoption of a regional constraint would undoubtedly cause global message processing problems.
(2) NormalResolvedSSILVA
In the mentioned example please note that there is no change in the date of flight identified in Item 18. The changes are in Items 8 and 16 as described in Field Type 22. It is agreed that in the messages concerned there is no useful reason to put all Item 18 information if there is no change in the referred Item. Field Type 18 in a CHG message shall not contain the changes. They go in Field Type 22. Field Type 18 with DOF specified in such messages it is meant to uniquely identify the flight when the FPL is presented more than 24 hours in advance and there is no need to include all the other Item 18 information in those messages.
2013-11-05 12:00 AM
A-7) Discrepancies exist between the Item 18 TYP/ data shown for the Flight Plan and that shown for ATS messages. The meeting sought clarification in respect to the use or non-use of commas between aircraft types, noting that the Flight Plan (page 16 of Amendment 1) indicates that
TYP/ Type(s) of aircraft, preceded if necessary without a space by number(s) of aircraft and separated
by one space, if ZZZZ is inserted in Item 9.
Example: TYP/2F15 5F5 3B2

whereas, the ATS message (page 30 of Amendment 1) includes commas between aircraft types, as shown below:
TYP/ Type(s) of aircraft, preceded if necessary without a space by number(s) of aircraft and separated
by one space, if ZZZZ is inserted in Item 9.
Example: –TYP/2F15, 5F5, 3B2

(2) NormalResolvedSSILVA
The comments are accepted and in the published version the comas from Field Type 18, TYP/ on page 30 will be removed.
2013-11-05 12:00 AM
A-8) The meeting noted that neither the PRESENT or NEW provisions made allowance for an equipment field in Section 6 & 7 of Appendix 2 of the PANS-ATM, in relation to Repetitive Flight Plans (RPL). The absence of such a field had led to local arrangements being agreed within and between some States in some instances to enable equipage to be notified in RPLs.
The meeting was of the view that having information in relation to equipage was of importance in RPL arrangements and sought ways to formalise the situation. Clarification was sought as to whether it was possible to include an equipment field in RPL, or whether the Task Force should pursue a regional constraint as part of the implementation process.
(2) NormalClosedSSILVA
The amendment didn’t change the RPL provisions. Historically it is assumed that aircraft filing a RPL are 'S' equipped for the route to be flown. Regional arrangement, like the use of EQPT/ to provide Field 10 info within Item Q of the RPL could be a Regional solution if deemed necessary.

The amendment didn’t change the RPL provisions. Historically it is assumed that aircraft filing a RPL are 'S' equipped for the route to be flown. Regional arrangement, like the use of EQPT/ to provide Field 10 info within Item Q of the RPL could be a Regional solution if deemed necessary.
2013-11-05 12:00 AM
E1) When there is a need to include the DOF/ indicator in the FPL message?
(2) NormalClosedSSILVA
Note: If in the CHG message the change is for the date of flight (DOF) insert the complete and amended data of the Item 18 in Field Type 22.
Examples of messages with/without DOF/.

Modification (CHG) Messages
o (CHG-ABC123-NZAA2300-VTBS-DOF/091120-16/VTBD1151 VTBD)
o (CHG-ABC123-NZAA2300-VTBS-0-16/VTBD1151 VTBD)
o (CHG-ABC123-NZAA2300-VTBS-DOF/091120-3/NZAA0045- 18/DOF/091121)

Flight Plan Cancellation (CNL) Messages
o (CNL-ABC123-NZAA2300-VTBS-DOF/091120)
o (CNL-ABC123-NZAA2300-VTBS-0)
Delay (DLA) Messages
o (DLA-ABC123-NZAA2345-VTBS-DOF/091120)
o (DLA-ABC123-NZAA2345-VTBS-0)
Departure (DEP) Messages
o (DEP-ABC123/A0254-NZAA2347-VTBS-DOF/091120)
o (DEP-ABC123/A0254-NZAA2347-VTBS-0)
Request Flight Plan (RQP) Messages
o (RQP-ABC123-NZAA2345-VTBS-DOF/091120)
o (RQP-ABC123-NZAA2345-VTBS-0)
o (RQP-ABC123-NZAA-VTBS-DOF/091120)
Request Supplementary Flight Plan (RQS) MessagesArrival (ARR) Messages
o (ARR-ABC123-NZAA-VTBS1315)
o (ARR-ABC123-NZAA0145-VTBS1315)

It is recommended that the DOF is inserted in all FPLs, and for FPLs filed more than 24H in advance it is mandatory.
It is recommended to use CHG if a flight is delayed over midnight UTC, indicating in field 22 amendments to both Fields 13b & 18, the EOBT and the DOF/.
The new EOBT provided in a DLA shall always be understood as a time that is later than the previously notified EOBT.
The DOF provided within Field 18 of associated messages shall always be the same as the previously notified DOF, to be used for associating the message to the correct flight.
If the original message does not specify DOF/, the associated messages shall include (-0-) in field type 18. This is to be in accordance with what is prescribed today in PANS-ATM that says that “Each message shall contain all the fields prescribed.” And this was not changed.

2013-11-05 12:00 AM
E2) The text for 13b states “transmitted before departure” – how can an ARR message be transmitted before departure?
(2) NormalClosedSSILVA
"before departure”, must be complemented with  “when applicable”. In this case the ARR message will not be transmitted before departure.
2013-11-05 12:00 AM
There is ongoing matter in relation to whether “J” would be
confirmed as a wake turbulence designator considering the numbers of A380 aircraft operating continued to increase.
(2) NormalClosedSSILVA
Although there is a group still studying the subject of wake turbulence designators it is reccomended to take advantage of the need to code software for the Amendment 1 implementation to also code the “J” wake turbulence designator. This would result in cost and effort savings for States and ANSPs.
2013-11-05 12:00 AM
A-10) E and L entries appear to be redundant
with items B1 and B2.
(2) NormalClosedSSILVA
E and L entries are for Mode S and B1/B2 covers only ADS-B capability, not covering Mode S. Therefore, there is no redundancy.
2013-11-05 12:00 AM
E-3) In the table of conversion, the 'new' Field 18 DAT/ indicator can contain free text and therefore cannot be converted into the 'current' DAT/ which is limited to the characters 'S', 'H', 'V', 'M'.
(2) NormalClosedSSILVA
The link which will be used by the system to transmit the information must be the one converted and informed, e.g., DAT/S, DAT/V, etc.
2013-11-05 12:00 AM
E-4) The translation of the Item 10a descriptors E1-E3 indicates use of the 'J' in Field 10a with a DAT/ indication in Field 18. As the 'current' DAT/ element is limited to 'S', 'H', 'V', 'M' this approach doesn't seem appropriate.
(2) NormalClosedSSILVA
The link used by the ACARS system to trasnsmit the information will be the one to be informed, e.g., DAT/V; DAT/H, etc.