User's Guide

Table Of Contents
User Guide for the Envoy Data Link
Document Number: UG-15000 Rev. A Page 110 of 173
Appendix C Supported CPDLC Messages
The Envoy supports the CPDLC message elements detailed in the following sections:
CPDLC Downlink Message Elements
CPDLC Uplink Message Elements
Where applicable, optional preformatted text may be combined to form a message with up to 5
elements.
C.1 CPDLC Downlink Message Elements
The FANS 1/A+ A/1 and ATN B1 CPDLC downlink messages in this appendix are supported by
Envoy.
The following highlights identify CPDLC protocol-specific messaging support:
FANS and ATN B1 common
FANS only
ATN B1 only
Appendix Table 1 CPLDC Downlink Message (DM) Format
Section
ID
CPDLC DM/Example
Message Intent
PANS/GOLD
3.4.3.1
0 WILCO
The instruction is understood and
will be complied with.
4.6-18
Responses
1 UNABLE
The instruction cannot be complied
with.
2
STANDBY
Wait for a reply.
3
ROGER
Message received and understood.
4
AFFIRM
Yes.
5
NEGATIVE
No.
3.5.1.1
6
REQUEST [level]
REQUEST FL250
Request to fly at the specified
level.
4.6-19 Vertical
Requests
7
REQUEST BLOCK [level] TO
[level]
REQUEST BLOCK 20000FT
TO 25000FT
Request to fly at a level within the
specified vertical range.
8
REQUEST CRUISE CLIMB TO
[level]
REQUEST CRUISE CLIMB TO
FL250
Request to cruise climb to the
specified level.
9
REQUEST CLIMB TO [level]
REQUEST CLIMB TO
25000FT
Request to climb to the specified
level.
10
REQUEST DESCENT TO
[level]
REQUEST DESCENT TO
20000FT
Request to descend to the
specified level.
11
AT [position] REQUEST CLIMB
TO [level]
AT XYZ REQUEST CLIMB TO
25000FT
Request that at the specified
position a climb to the specified
level be approved.