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
Delay (DLA) Messages
Departure (DEP) Messages
Request Flight Plan (RQP) Messages
Request Supplementary Flight Plan (RQS) Messages
Arrival (ARR) Messages
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.