Title:  CPDLC vs. ICAO Doc 4444, Amd 2 comparison

PDR Reference:				98100001
Originator Reference: 			4444-9705
SARPs Document Reference:  		2.3.4, 2.3.7
Status: 					RESOLVED
Impact:					C (Clarification)
PDR Revision Date:			17/05/99 (see added item 70)
						18/01/99 (PROPOSED -> RESOLVED)
						08/12/98: alternative change for chapter 7
						23/11/98
						chapter 4: changes: 14, 14a
						chapter 7: changes: 4a, 4b, 6a, 17a, 20,33a, 
                                  	40, 47, 48, 49, 50a, 53a, 60, 61a, 64, 66a, 						68 
						13/11/98 (SUBMITTED -> ACCEPTED -> PROPOSED)
PDR Submission Date:  			31/10/98
Submitting State/Organization: 	USA
Submitting Author Name: 		Van Trees, SP
Submitting Author E-mail Address: 	stephen.van.trees@faa.gov
Submitting Author Supplemental 
Contact Information:			FAA/AIR-130, Room 815
						800 Independence Avenue, SW
						Washington, DC 20591-0004
						USA
						+1.202.267.9567
						+1.202.267.5340 (fax)
SARPs Date: 				ICAO Doc 9705, Edition 1.  
						ICAO Doc 4444, Amendment 2.
SARPs Language:  				English

Summary of Defect: 

The ICAO Doc 4444 (PANS-RAC) definition and ICAO Doc 9705 definition of CPDLC would appear to differ in some details.

The current version of Doc 4444 is Thirteenth Edition - 1996, up to and including Amendment 2.  Amd 2, which only became applicable on 5/11/98, includes the complete CPDLC message set as Appendix 5.

Doc 9705 Edition 1 CPDLC Chapter 7 (User Requirements) is aligned with a previous draft of this Annex, which was modified after States requested some: changes in their response to the State Letter (10/97) and approved by ICAO council (02/98).

Some message attributes (specified in Doc 9705 Edition 1 CPDLC Chapter 4 as ASN.1 comments) do not correspond to those specified in Chapter 7.

Assigned SME:  				Sub-Volume II SME

Proposed SARPs amendment (see file "9810001a.wpd" in directory atnp/ccb/sme2). 

Chapter 4:
1.  uM0  : change Alr(L) to Alr(M)
2.  uM41 : change Resp(W/Y) to Resp (Y)
3.  uM127, uM128, uM129, and uM130: change Alr(M) to Alr(L)
4.  uM131: change Urg(N) to Urg(U)
5.  uM135 through and including uM144: change Alr(M) to Alr(L)
6.  uM148 through and including uM154: change Alr(M) to Alr(L)
7.  uM158: change Alr(M) to Alr(L)
8.  uM168: change Urg(N) to Urg(U)
9.  uM175: change Alr(M) to Alr(L)
10. uM180: change Alr(M) to Alr(L)
11. uM182: change Alr(M) to Alr(L)
12. uM184: change Alr(M) to Alr(L)
13. uM200: change Alr(M) to Alr(L)and: change Rsp(R)to Rsp(W/U)
14. uM212 and uM213: change Alr(M) to Alr(L)
14a.uM232: change "STATE-TOP-OF-DESCENT" to "STATE TOP OF DESCENT"
15. dM26  and dM27: change Alr(L) to Alr(M)
16. dM29  through and including dM37: change Alr(M) to Alr(L)
17. dM42  through and including dM47: change Alr(M) to Alr(L)
18. dM72 : change Alr(M) to Alr(L)
19. dM76 : change Alr(N) to Alr(L)
20. dM77 : change Alr(N) to Alr(M)
21. dM78 : change Alr(N) to Alr(L)
22. dM79 : change Alr(M) to Alr(L)
23. dM81  through and including dM86: change Urg(N) to Urg(L)
24. dM89 : change Urg(L) to Urg(U)
25. dM103: change Alr(N) to Alr(L).

For Chapter 7, two alternative changes are proposed to CCB:

I - ALIGN Doc 9705 Ed. 1 CHAPTER 7
==================================
Note. The changes numbered without extension (1,2,..., 69) identify differences between Doc 9705 Ed1 and the Doc 4444 final softcopy version from the ADS Secretary. The changes numbered with an extension (a,b,..) identify changes between the final softcopy version of the ADS Secretary and the hardcopy version sent to the States by ICAO.

0. Delete Section 2.3.7.1 Note 5 which indicates that in case of inconsistencies between Doc 4444 and Doc 9705 Doc 4444 takes precedence.

In Table 2.3.7-5:
1. uM0, uM1, uM2, uM3: change "ATS" to "ATC"
2. uM211: change "ATS" to "ATC" and change "Next Control Authority" to "next control authority"

In Table 2.3.7-6:
3.  uM7 through and including uM18: delete the extra space between the words "for and "the"
4.  uM20: change "and the level is to be maintained when reached." to "and once reached the specified level is to be maintained."
4a. uM21: change "at the specified time," to "at the specified time"
4b. uM22, uM185, uM186: change "at the specified position," to "at the specified position"
5.  uM23: change "and the level is to be maintained when reached." to "and once reached the specified level is to be maintained."
6.  uM25: change "and when the specified level is reached it is to be maintained." to "and once reached the specified level is to be maintained."
6a. uM209: change "position" to "position."
7.  uM30: change "A level" to "Instruction that a level"
8.  uM34, uM35: change "A cruise" to "Instruction that a cruise"
9.  uM220: delete a space between "level" and the period ".".
10. uM36: change "The climb" to "Instruction that the climb"
11. uM37: change "The descent" to "Instruction that the descent"
12. uM40: change "Urgent instruction to immediately stop a climb once the specified level is reached." To "(reserved)"; delete "IMMEDIATELY STOP CLIMB AT [level]" in the "Message Element" column and leave the cell blank; change "D" to "L" and "H" to "L" and "W/U" to "Y" in the last three cells respectively.
13. uM41: change "Urgent instruction to immediately stop a descent once the specified level is reached." To "(reserved)"; delete "IMMEDIATELY STOP DESCENT AT [level]" in the "Message Element" column and leave the cell blank; change "D" to "L" and "H" to "L" and "W/U" to "Y" in the last three cells respectively.
14. uM171: delete one of the spaces between "than" and "the"
15. uM33: change "Reserved." to "(reserved)" and insert "L", "L", and "Y" in the last three cells respectively.
16. At the bottom of Table 2.3.7-6 insert the note in italics as indicated:  
"Note.- Wherever the variable "level" is specified, the message can specify either a single level or a vertical range, i.e. block level."

In Table 2.3.7-7:
17. uM46, uM47, uM48, uM50: through and including uM60 change "The specified" to "Instruction that the specified"
17a. uM61, uM63: change "and speed and" to "and speed, and"
18. At the bottom of Table 2.3.7-7 insert the note in italics as indicated:  
"Note.- Wherever the variable "level" is specified, the message can specify either a single level or a vertical range, i.e. block level."

In Table 2.3.7-8:
19. uM67, uM68, uM69: change "The cleared" to "Instruction that the cleared"

In Table 2.3.7-9:
20. uM94, uM95, uM98: change "onto" to "on to"
21. At the bottom of Table 2.3.7-9 insert the note in italics as indicated:  
"Note.- Wherever the variable "level" is specified, the message can specify either a single level or a vertical range, i.e. block level."

In Table 2.3.7-10:
22. uM106,uM108,uM109,uM115: change "The specified" to "Instruction that the specified"
23. uM188: change "After passing" to "Instruction that after passing"
24. uM107, uM111 through and including uM114, uM189: change "The present" to "Instruction that the present"
25. uM110: change "A speed" to "Instruction that a speed"
26. uM222: change "Instruction" to "Notification", and delete one of two spaces before the word "that"
26a. uM223: change "approach speed" to "approach speed."
27. At the bottom of Table 2.3.7-10 insert the note in italics as indicated:  
"Note.- Wherever the variable "level" is specified, the message can specify either a single level or a vertical range, i.e. block level."

In Table 2.3.7-11:
28. uM117, uM120: change "The ATS" to "Instruction that the ATS"
29. uM118, uM119, uM121, uM122: change "At the" to "Instruction that at the"
30. uM123: change "The specified" to "Instruction that the specified"
31. uM124, uM125, uM126: change "The SSR" to "Instruction that the SSR"
32. uM179: change "The 'ident' " to "Instruction that the 'ident' "

In Table 2.3.7-12:
33. Move uM200 from Table 2.3.7-16 to Table 2.3.7-12 and insert it between uM175 and uM180
33a. uM200: change "Used in" to "Instruction used in"

33b and change the "R" in the last cell to a "W/U"
34. uM228: delete one of two space between the words "report" and "the" and add a period after the word "position" at the end of the sentence
35. uM144: change "code (SSR)" to "(SSR) code"
36. At the bottom of Table 2.3.7-12 insert the note in italics as indicated:  
"Note.- Wherever the variable "level" is specified, the message can specify either a single level or a vertical range, i.e. block level."

In Table 2.3.7-13:
37. At the bottom of Table 2.3.7-13 insert the note in italics as indicated:  
"Note.- Wherever the variable "level" is specified, the message can specify either a single level or a vertical range, i.e. block level."

In Table 2.3.7-14:
38. uM193: change "Indication" to "Notification"
39. uM157: change "A continuous" to "Notification that a continuous"

In Table 2.3.7-15:
40. uM160: change "next" to "specified" and "specified ATSU" to "next data authority.  If no data authority is specified, this indicates that any previously specified next data authority is no longer valid."

In Table 2.3.7-16:
41. uM176: change "operator" to "pilot" and change "Visual Meteorological Conditions" to "visual meteorological conditions"
42. uM177: change "operator" to "pilot"
43. Move uM178 to between the uM177 and uM169; then in the "Message Intent/Use" column add the word "(reserved)" and delete "[free text]" in column "Message Element" and change "N" to "L" on the third from last cell and change "N" to "Y" in the last cell.
44. Move uM183 to between the uM170 and uM194
45. Move uM187 to between the newly moved uM183 and uM194 (Table 2.3.7-16)
46. uM199: change "M" to "L" and "W/U" to "N" in the last two cells respectively
47. uM201: change "Not Used." to "Not used" (no italics, no period)
48. uM202: add "Not used", and delete "[free text]" in column "Message Element" and change "D" to "L" and "H" to "L" and "W/U" to "N" in the last three cells respectively.
49. At the bottom of Table 2.3.7-16 insert the note in italics as indicated:  
"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."

In Table 2.3.7-18:
50. At the bottom of Table 2.3.7-18 insert the note in italics as indicated:  
"Note.- Wherever the variable "level" is specified, the message can specify either a single level or a vertical range, i.e. block level."

In Table 2.3.7-23:
50a. dM78: change "At the specified time" to "Notification that at the specified time"
51. dM37 ("Message Element"): change "LEVEL" to "MAINTAINING"
52. dM47: change "specified code" to "specified (SSR) code"
53. dM89: change "ICAO" to "ATS"
53a. dM111 ("Message Element"): change "position]" to "[position]"
54. At the bottom of Table 2.3.7-23 insert the note in italics as indicated:  
"Note.- Wherever the variable "level" is specified, the message can specify either a single level or a vertical range, i.e. block level."

In Table 2.3.7-24:
55. At the bottom of Table 2.3.7-24 insert the note in italics as indicated:  
"Note.- Wherever the variable "level" is specified, the message can specify either a single level or a vertical range, i.e. block level."

In Table 2.3.7-25:
56. dM57: change "N" to "Y" in the last cell
57. dM59: change "specified route" to "specified route due to an urgent need"
58. dM60: change "parallel track" to "parallel track due to an urgent need"
59. dM61: change "specified level" to "specified level due to an urgent need"
60. dM80: replace the "Message Intent/Use" column by "Notification that the aircraft is deviating up to the specified distance from the cleared route in the specified direction due to an urgent need"
61. At the bottom of Table 2.3.7-25 insert the note in italics as indicated:  
"Note.- Wherever the variable "level" is specified, the message can specify either a single level or a vertical range, i.e. block level."

In Table 2.3.7-26:
61a. dM62,dM63,dM19,dM107,dM73: change "system generated" to "system-generated"
62. dM63, dM99: change "Current Data Authority" to "current data authority"

63. Switch the order of dM107 and dM64 
64. dM100: change "Notification" to "Confirmation" and "acknowledgment refers." to "acknowledgment refers and found it acceptable for display to the responsible person."

In Table 2.3.7-27:
65. dM65, dM66: change "aircraft operator's" to "pilot's"
66. dM74, dM101, dM103: change "aircraft operator" to "pilot"
66a. dM103: change "canceled" to "cancelled"
67. dM75: change "operator" to "pilot"
68. At the bottom of Table 2.3.7-27 insert the note in italics as indicated:  
"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."

In Table 2.3.7-28:
69. At the bottom of the table 2.3.7-28 insert the note in italics as indicated:  
"Note.- Wherever the variable "level" is specified, the message can specify either a single level or a vertical range, i.e. block level."

70. Add note2 to section 2.3.7.6.1 and renumber existing note as note 1 as follows:
Note 2.- Tables 2.3.7-5 to 2.3.7-28 which are aligned with provisions contained in Appendix 5 of the 13th Edition of ICAO Doc 4444 - Procedures for Air Navigation Services - Rules of the Air and Air Traffic Services (PANS-RAC) are included in this document for completeness. 

II - REMOVE THE TABLES FROM Doc 9705 Ed. 1 CHAPTER 7
====================================================
Since Doc 4444 Amd2 is now published, it is now possible to refer to it unambiguously. 

1. Delete sections 2.3.7.6.1, 2.3.7.6.2 and 2.3.7.6.3
2. Add the following note in italics to 2.3.7.6 as follows:

Note.- The message set for CPDLC is contained in Appendix 5 of ICAO DOC 4444 (Rules of the Air and Air Traffic Services) 13th Edition, (including Amendment 2, dated 5 November 1998).  Message attributes, message presentation guidance, and data structure presentation guidance are presented herein.  The actual information exchanged between an aircraft and ground peer or a ground and ground peer CPDLC applications is defined in 2.3.4 above; however, 2.3.4 does not mandate any particular method for presenting this information.  The presentation of information to the controller and aircraft crew is a local implementation.  The message presentation recommendations contained in  Doc 4444 Appendix 5 are one possible means of presenting the information.  These recommendations are generally consistent with current ICAO practices for displaying ATC information.

3. Add new 2.3.7.6.1 as follows:
2.3.7.6.1	 Message elements shall comply with the intent, use, and element attributes as presented in Doc 4444 Appendix 5.

Impact on interoperability: There is no impact on interoperability since the changes apply to ASN.1 comments in chapter 4 and to requirements in chapter 7.

SME Recommendation to CCB:  		

CCB Decision:  		atnp_ccb_chair: SUBMITTED (02/11/98)
				atnp_ccb_chair: ACCEPTED (13/11/98)
				CCB-8 (Honolulu): RESOLVED with solution 1 (18/01/99)
				CCB-9 (Naples): Add a new note (see item 70)