Appendix F Operational Definition in PANS-ATM (Doc 4444) CPDLC Message Sets Message Element Identifier Message Element Intended Use Format for Message Element Display Resp. FANS 1/A ATN B1 LVLU-14 Instruction that a descent is to be completed such that the specified level is reached before the specified time.
DESCEND TO REACH (level single) BEFORE TIME (time) W/U UM28 DESCEND TO REACH (altitude) BY (time) UM28 DESCEND TO REACH (level) BY (time) LVLU-15 Instruction that a descent is to be completed such that the specified level is reached before passing the specified position.
DESCEND TO REACH (level single) BEFORE PASSING (position) W/U UM29 DESCEND TO REACH (altitude) BY (position) UM29 DESCEND TO REACH (level) BY (position) LVLU-16 Instruction to stop the climb at the specified level and, once reached, this level is to be maintained. The specified level will be below the previously assigned level. This instruction should only be issued when the controller can confirm that the previously assigned level has not yet been reached.
STOP CLIMB AT (level single) W/U UM169 ‘STOP CLIMB AT (altitude)’ Note: R response attribute.
N/A LVLU-17 Instruction to stop the descent at the specified level and, once reached, this level is to be maintained. The specified level will be above the previously assigned level. This instruction should only be issued when the controller can confirm that the previously assigned level has not yet been reached.
STOP DESCENT AT (level single) W/U UM169 ‘STOP
DESCENT AT (altitude)’ Note: R response attribute.
N/A LVLU-18 Instruction to climb at the specified rate or greater.
CLIMB AT (vertical rate) OR
GREATER W/U UM171 CLIMB AT (vertical rate)
MINIMUM UM171 CLIMB AT (vertical rate)
MINIMUM F-17
Appendix F Operational Definition in PANS-ATM (Doc 4444) CPDLC Message Sets Message Element Identifier Message Element Intended Use Format for Message Element Display Resp. FANS 1/A ATN B1 LVLU-19 Instruction to climb at the specified rate or less.
CLIMB AT (vertical rate) OR LESS W/U UM172 CLIMB AT (vertical rate)
MAXIMUM UM172 CLIMB AT (vertical rate)
MAXIMUM LVLU-20 Instruction to descend at the specified rate or greater.
DESCEND AT (vertical rate)
OR GREATER W/U UM173 DESCEND AT (vertical rate)
MINIMUM UM173 DESCEND AT (vertical rate)
MINIMUM LVLU-21 Instruction to descend at the specified rate or less.
DESCEND AT (vertical rate)
OR LESS W/U UM174 DESCEND AT (vertical rate)
MAXIMUM UM174 DESCEND AT (vertical rate)
MAXIMUM LVLU-22 Notification that a clearance may be issued for the aircraft to commence a climb to the specified level at the specified number of minutes after departure.
EXPECT (level single) (number of minutes) AFTER
DEPARTURE R UM169 ‘EXPECT (level single) (number of minutes) AFTER DEPARTURE’ N/A LVLU-23 Instruction to report upon leaving the specified level.
REPORT LEAVING (level single) W/U UM128 REPORT LEAVING (altitude) Note: R response attribute.
N/A LVLU-24 Instruction to report upon maintaining the specified level.
REPORT MAINTAINING (level single) W/U UM129 REPORT LEVEL (altitude) Note: R response attribute.
N/A LVLU-25 Instruction to report the present level.
REPORT PRESENT LEVEL Y N/A Note: Refer to A.6.
UM133 REPORT
PRESENT LEVEL LVLU-26 Instruction to report upon reaching the specified vertical range.
REPORT REACHING BLOCK (level single) TO (level single) W/U UM180 REACHING BLOCK (altitude) TO (altitude) Note: R response attribute.
N/A F-18
Appendix F Operational Definition in PANS-ATM (Doc 4444) CPDLC Message Sets Message Element Identifier Message Element Intended Use Format for Message Element Display Resp. FANS 1/A ATN B1 LVLU-27 Request to confirm the assigned level.
CONFIRM ASSIGNED LEVEL Y UM135 CONFIRM
ASSIGNED
ALTITUDE Note: NE response attribute.
N/A LVLU-28 Request to provide the preferred level.
ADVISE PREFERRED LEVEL Y UM169 ‘ADVISE
PREFERRED LEVEL’ Note: R response attribute.
UM231 STATE
PREFERRED LEVEL LVLU-29 Request to provide the preferred time and/or position to commence descent to the aerodrome of intended arrival.
ADVISE TOP OF DESCENT Y UM169 ‘ADVISE TOP OF DESCENT’ Note: R response attribute.
UM232 STATE TOP
OF DESCENT LVLU-30 Request for the earliest time or position when the specified level can be accepted.
WHEN CAN YOU ACCEPT (level single) Y UM148 WHEN CAN
YOU ACCEPT (altitude) Note: NE response attribute.
UM148 WHEN CAN YOU ACCEPT (level) LVLU-31 Request to indicate whether or not the specified level can be accepted at the specified position.
CAN YOU ACCEPT (level single) AT (position) A/N UM149 CAN YOU ACCEPT (altitude) AT (position) N/A LVLU-32 Request to indicate whether or not the specified level can be accepted at the specified time.
CAN YOU ACCEPT (level single) AT TIME (time) A/N UM150 CAN YOU ACCEPT (altitude) AT (time) N/A LVLU-33 Instruction to expedite a descent to the specified level is to commence and once reached the specified level is to be maintained.
EXPEDITE DESCENT TO (level single) W/U UM37 EXPEDITE
DESCENT TO (altitude) N/A F-19
Appendix F Table F-9. Level Downlink Message Elements (LVLD) Operational Definition in PANS-ATM (Doc 4444) CPDLC Message Sets Message Element Identifier Message Element Intended Use Format for Message Element Display Resp. FANS 1/A ATN B1 LVLD-1 Request to fly at the specified level or vertical range.
REQUEST (level) Y DM6 REQUEST (altitude) Note: Used for a single level.
DM7 REQUEST BLOCK (altitude) TO (altitude) Note: Used for a vertical range.
DM6 REQUEST (level) LVLD-2 Request for a climb to the specified level or vertical range.
REQUEST CLIMB TO (level) Y DM9 REQUEST CLIMB TO (altitude) Note: Use of DM7
REQUEST BLOCK (altitude) TO (altitude) to request to climb at a vertical range.
DM9 REQUEST CLIMB TO (level) LVLD-3 Request for a descent to the specified level or vertical range.
REQUEST DESCENT TO (level) Y DM10 REQUEST DESCENT TO (altitude) Note: Use of DM7
REQUEST BLOCK (altitude) TO (altitude) to request to descend at a vertical range.
DM10 REQUEST DESCENT TO (level) F-20
Appendix F Operational Definition in PANS-ATM (Doc 4444) CPDLC Message Sets Message Element Identifier Message Element Intended Use Format for Message Element Display Resp. FANS 1/A ATN B1 LVLD-4 Request for a climb/descent to the specified level or vertical range to commence at the specified position.
AT (position) REQUEST (level) Y DM11 AT (position)
REQUEST CLIMB TO (altitude) Note: A vertical range cannot be requested.
DM12 AT (position)
REQUEST DESCENT TO (altitude) Note: A vertical range cannot be requested.
N/A LVLD-5 Request for a climb/descent to the specified level or vertical range to commence at the specified time.
AT TIME (time) REQUEST (level) Y DM13 AT TIME (time)
REQUEST CLIMB TO (altitude) Note: A vertical range cannot be requested.
DM14 AT TIME (time)
REQUEST DESCENT TO (altitude) Note: A vertical range cannot be requested.
N/A LVLD-6 Request for the earliest time or position that a descent can be expected.
WHEN CAN WE EXPECT
LOWER LEVEL Y DM52 WHEN CAN WE
EXPECT LOWER
ALTITUDE N/A LVLD-7 Request for the earliest time or position that a climb can be expected.
WHEN CAN WE EXPECT
HIGHER LEVEL Y DM53 WHEN CAN WE
EXPECT HIGHER
ALTITUDE N/A LVLD-8 Report indicating leaving the specified level.
LEAVING (level single) N DM28 LEAVING (altitude) N/A LVLD-9 Report indicating that the specified level is being maintained.
MAINTAINING (level single) N DM37 LEVEL (altitude) N/A F-21
Appendix F Operational Definition in PANS-ATM (Doc 4444) CPDLC Message Sets Message Element Identifier Message Element Intended Use Format for Message Element Display Resp. FANS 1/A ATN B1 LVLD-10 Report indicating reaching the specified vertical range.
REACHING BLOCK (level single) TO (level single) N DM76 REACHING BLOCK (altitude) TO (altitude) N/A LVLD-11 Confirmation that the assigned level or vertical range is the specified level or vertical range.
ASSIGNED LEVEL (level) N DM38 ASSIGNED ALTITUDE (altitude) Note: Used for a single level.
DM77 ASSIGNED BLOCK (altitude) TO (altitude) Note: Used for a vertical range.
DM38 ASSIGNED LEVEL (level) LVLD-12 Report indicating that the aircraft’s preferred level is the specified level.
PREFERRED LEVEL (level single) N DM67‘PREFERRED LEVEL (altitude)’ Note 1: Response to free text UM169 ‘ADVISE PREFERRED LEVEL’ Note 2: When pre-formatting of the downlink message is not available, the pilot can shorten to: FL (altitude).
DM106 PREFERRED LEVEL (level) Note A vertical range may be provided.
LVLD-13 Report indicating climbing to the specified level.
CLIMBING TO (level single) N DM29 CLIMBING TO (altitude) N/A F-22
Appendix F Operational Definition in PANS-ATM (Doc 4444) CPDLC Message Sets Message Element Identifier Message Element Intended Use Format for Message Element Display Resp. FANS 1/A ATN B1 LVLD-14 Report indicating descending to the specified level.
DESCENDING TO (level single) N DM30 DESCENDING TO (altitude) Note: N alert attribute.
DM61 DESCENDING TO (altitude) Note: Urgent alert attribute.
N/A LVLD-15 Indication that the specified level can be accepted at the specified time.
WE CAN ACCEPT (level single) AT TIME (time) N DM67 ‘WE CAN ACCEPT (altitude) AT TIME (time)’ DM81 WE CAN ACCEPT (level) AT (time) Note: A vertical range may be provided.
LVLD-16 Indication that the specified level can be accepted at the specified position.
WE CAN ACCEPT (level single) AT (position) N DM67 ‘WE CAN ACCEPT (altitude) AT (position)’ N/A LVLD-17 Indication that the specified level cannot be accepted.
WE CANNOT ACCEPT (level single) N DM67. ‘WE CANNOT ACCEPT (altitude)’ DM82 WE CANNOT ACCEPT (level) Note: A vertical range may be provided.
LVLD-18 Notification of the preferred time and position to commence descent for approach.
TOP OF DESCENT (position) TIME (time) N DM67 ‘TOP OF DESCENT (time)’ Note: When pre-formatting of the downlink message is not available, the pilot can shorten to:
TOD (time).
DM109 TOP OF DESCENT (time) LVLD-19 Notification of the present level. Present level (single level) N N/A Note: Refer to A.6.
DM32 PRESENT LEVEL (altitude) F-23
Appendix F Table F-10. Crossing Constraint Uplink Messages (CSTU) Operational Definition in PANS-ATM (Doc 4444) CPDLC Message Sets Message Element Identifier Message Element Intended Use Format for Message Element Display Resp. FANS 1/A ATN B1 CSTU-1 Instruction that the specified position is to be crossed at the specified level or within the specified vertical range.
CROSS (position) AT (level) W/U UM46 CROSS (position) AT (altitude) Note: Used for a single level.
UM46 CROSS (position) AT (level) CSTU-1 Instruction that the specified position is to be crossed at the specified level or within the specified vertical range.
CROSS (position) AT (level) UM50 CROSS (position) BETWEEN (altitude) AND (altitude) Note: Used for a vertical range.
UM46 CROSS (position) AT (level) CSTU-1 Instruction that the specified position is to be crossed at the specified level or within the specified vertical range.
CROSS (position) AT (level) W/U UM49 CROSS (position) AT
AND MAINTAIN (altitude) Note 1: A vertical range cannot be provided.
Note 2: This message element is equivalent to CSTU-1 plus LVLU-5 in ICAO Doc 4444.
N/A CSTU-2 Instruction that the specified position is to be crossed at or above the specified level.
CROSS (position) AT OR ABOVE (level single) W/U UM47 CROSS (position) AT OR ABOVE (altitude) UM47 CROSS (position) AT OR ABOVE (level) CSTU-3 Instruction that the specified position is to be crossed at or below the specified level.
CROSS (position) AT OR BELOW (level single) W/U UM48 CROSS (position) AT OR BELOW (altitude) UM48 CROSS (position) AT OR BELOW (level) F-24
Appendix F Operational Definition in PANS-ATM (Doc 4444) CPDLC Message Sets Message Element Identifier Message Element Intended Use Format for Message Element Display Resp. FANS 1/A ATN B1 CSTU-4 Instruction that the specified position is to be crossed at the specified time.
CROSS (position) AT TIME (time) W/U UM51 CROSS (position) AT (time) UM51 CROSS (position) AT (time) CSTU-5 Instruction that the specified position is to be crossed before the specified time.
CROSS (position) BEFORE TIME (time) W/U UM52 CROSS (position) AT OR BEFORE (time) UM52 CROSS (position) AT OR BEFORE (time) CSTU-6 Instruction that the specified position is to be crossed after the specified time.
CROSS (position) AFTER TIME (time) W/U UM53 CROSS (position) AT OR AFTER (time) UM53 CROSS (position) AT OR AFTER (time) CSTU-7 Instruction that the specified position is to be crossed between the specified times.
CROSS (position) BETWEEN TIME (time) AND TIME (time) W/U UM54 CROSS (position) BETWEEN (time) AND (time) UM54 CROSS (position) BETWEEN (time) AND (time) CSTU-8 Instruction that the specified position is to be crossed at the specified speed.
CROSS (position) AT (speed) W/U UM55 CROSS (position) AT (speed) UM55 CROSS (position) AT (speed) CSTU-9 Instruction that the specified position is to be crossed at or less than the specified speed.
CROSS (position) AT (speed) OR LESS W/U UM56 CROSS (position) AT OR LESS THAN (speed) N/A CSTU-10 Instruction that the specified position is to be crossed at or greater than the specified speed.
CROSS (position) AT (speed) OR GREATER W/U UM57 CROSS (position) AT OR
GREATER THAN (speed) N/A F-25
Appendix F Operational Definition in PANS-ATM (Doc 4444) CPDLC Message Sets Message Element Identifier Message Element Intended Use Format for Message Element Display Resp. FANS 1/A ATN B1 CSTU-11 Instruction that the specified position is to be crossed at the specified time and at the level or within the vertical range as specified.
CROSS (position) AT TIME (time) AT (level) W/U UM58 CROSS (position) AT (time) AT (altitude) Note: A vertical range cannot be provided.
UM62 AT (time) CROSS (position) AT
AND MAINTAIN (altitude) Note 1: A vertical range cannot be provided.
Note 2: This message element is equivalent to CSTU-11 plus LVLU-5 in ICAO Doc 4444.
N/A CSTU-12 Instruction that the specified position is to be crossed before the specified time and at the level or within the vertical range as specified.
CROSS (position) BEFORE TIME (time) AT (level) W/U UM59 CROSS (position) AT OR BEFORE (time) AT (altitude) Note: A vertical range cannot be provided.
N/A CSTU-13 Instruction that the specified position is to be crossed after the specified time and at the level or within the vertical range as specified.
CROSS (position) AFTER TIME (time) AT (level) W/U UM60 CROSS (position) AT OR AFTER (time) AT (altitude) Note: A vertical range cannot be provided.
N/A F-26
Appendix F Operational Definition in PANS-ATM (Doc 4444) CPDLC Message Sets Message Element Identifier Message Element Intended Use Format for Message Element Display Resp. FANS 1/A ATN B1 CSTU-14 Instruction that the specified position is to be crossed at the level or within the vertical range, as specified, and at the specified speed.
CROSS (position) AT (level) AT (speed) W/U UM61 CROSS (position) AT AND MAINTAIN (altitude) AT (speed) Note 1: A vertical range cannot be provided.
Note 2: This message element is equivalent to CSTU-14 plus LVLU-5 in ICAO Doc 4444.
UM61 CROSS (position) AT AND MAINTAIN (level) AT (speed) CSTU-15 Instruction that the specified position is to be crossed at the specified time at the level or within the vertical range, as specified, and at the specified speed.
CROSS (position) AT TIME (time) AT (level) AT (speed) W/U UM63 AT (time) CROSS (position) AT
AND MAINTAIN (altitude) AT (speed) Note 1: A vertical range cannot be provided.
Note 2: This message element is equivalent to CSTU-15 plus LVLU-5 in ICAO Doc 4444.
N/A F-27
Appendix F Table F-11. Speed Uplink Messages (SPDU) Operational Definition in PANS-ATM (Doc 4444) CPDLC Message Sets Message Element Identifier Message Element Intended Use Format for Message Element Display Resp. FANS 1/A ATN B1 SPDU-1 Notification that a speed instruction may be issued to take effect at the specified time.
EXPECT SPEED CHANGE AT TIME (time) R UM100 AT (time) EXPECT (speed) N/A SPDU-2 Notification that a speed instruction may be issued to take effect at the specified position.
EXPECT SPEED CHANGE AT (position) R UM101 AT (position) EXPECT (speed) N/A SPDU-3 Notification that a speed instruction may be issued to take effect at the specified level.
EXPECT SPEED CHANGE AT (level single) R UM102 AT (altitude) EXPECT (speed) N/A SPDU-4 Instruction to maintain the specified speed.
MAINTAIN (speed) W/U UM106 MAINTAIN (speed) UM106 MAINTAIN (speed) SPDU-5 Instruction to maintain the present speed.
MAINTAIN PRESENT SPEED W/U UM107 MAINTAIN
PRESENT SPEED UM107 MAINTAIN
PRESENT SPEED SPDU-6 Instruction to maintain the specified speed or a greater.
MAINTAIN (speed) OR
GREATER W/U UM108 MAINTAIN (speed) OR
GREATER UM108 MAINTAIN (speed) OR
GREATER SPDU-7 Instruction to maintain the specified speed or a less.
MAINTAIN (speed) OR LESS W/U UM109 MAINTAIN (speed) OR LESS UM109 MAINTAIN (speed) OR LESS SPDU-8 Instruction to maintain the specified speed range.
MAINTAIN (speed) TO (speed) W/U UM110 MAINTAIN (speed) TO (speed) N/A SPDU-9 Instruction that the present speed is to be increased to the specified speed and maintained until further advised.
INCREASE SPEED TO (speed) W/U UM111 INCREASE SPEED TO (speed) N/A F-28