Note.— Free text message elements have no associated message intent. The capability to send a free text message with any of the attribute combinations already used in the message set has been provided for in the technical requirements of the ATN (Annex 10, Volume III, Part I, Chapter 3).
No. 3

Appendix 5 A5-19
2. Downlink messages
Table A5-13. Responses (downlink)

Message intent/use  Message element  URG  ALRT  RESP 
0  The instruction is understood and will be complied with.  WILCO  N  M  N 
1  The instruction cannot be complied with.  UNABLE  N  M  N 
2  Wait for a reply.  STANDBY  N  M  N 
3  Message received and understood.  ROGER  N  M  N 
4  Yes.  AFFIRM  N  M  N 
5  No.  NEGATIVE  N  M  N 

Table A5-14. Vertical requests (downlink)
Message intent/use  Message element  URG  ALRT  RESP 
6  Request to fly at the specified level.  REQUEST (level)  N  L  Y 
7  Request to fly at a level within the specified vertical range.  REQUEST BLOCK (level) TO (level)  N  L  Y 
8  Request to cruise climb to the specified level.  REQUEST CRUISE CLIMB TO (level)  N  L  Y 
9  Request to climb to the specified level.  REQUEST CLIMB TO (level)  N  L  Y 
10  Request to descend to the specified level.  REQUEST DESCENT TO (level)  N  L  Y 
11  Request that at the specified position a climb to the specified level be approved.  AT (position) REQUEST CLIMB TO (level)  N  L  Y 
12  Request that at the specified position a descent to the specified level be approved.  AT (position) REQUEST DESCENT TO (level)  N  L  Y 
13  Request that at the specified time a climb to the specified level be approved.  AT (time) REQUEST CLIMB TO (level)  N  L  Y 
14  Request that at the specified time a descent to the specified level be approved.  AT (time) REQUEST DESCENT TO (level)  N  L  Y 
69  Request that a descent be approved on a see-and-avoid basis.  REQUEST VMC DESCENT  N  L  Y 

Note.— Wherever the variable “level” is specified, the message can specify either a single level or a vertical range, i.e. block level.
No. 2

Table A5-15. Lateral offset requests (downlink)
Message intent/use  Message element  URG  ALRT  RESP 
15  Request that a parallel track, offset from the cleared track by the specified distance in the specified direction, be approved.  REQUEST OFFSET (specified distance) (direction) OF ROUTE  N  L  Y 
16  Request that a parallel track, offset from the cleared track by the specified distance in the specified direction, be approved from the specified position.  AT (position) REQUEST OFFSET (specified distance) (direction) OF ROUTE  N  L  Y 
17  Request that a parallel track, offset from the cleared track by the specified distance in the specified direction, be approved from the specified time.  AT (time) REQUEST OFFSET (specified distance) (direction) OF ROUTE  N  L  Y 

Table A5-16. Speed requests (downlink)
Message intent/use  Message element  URG  ALRT  RESP 
18  Request to fly at the specified speed.  REQUEST (speed)  N  L  Y 
19  Request to fly within the specified speed range.  REQUEST (speed) TO (speed)  N  L  Y 
　
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