Title: CPDLC - Revision on Position Definition for Latitude/Longitude

PDR Reference: 				97060011
Originator Reference: 			PDRPOS
SARPs Document Reference: 		CPDLC SARPs, Section 2.3.4.2.1
Status: 				      ADOPTED
PDR Revision Date: 			22/09/97 (SUBMITTED -> ACCEPTED)
						22/09/97 (ACCEPTED -> PROPOSED)
						20/10/97 (PROPOSED -> RESOLVED)
PDR Submission Date:			27/06/97
Submitting State/Organization: 		ATNP WG3/SG2
Submitting Author Name: 		Hamelink, J
Submitting Author E-mail Address: 	Jhamelin@adsystech.com
Submitting Author Supplemental 
Contact Information:
SARPs Date: 				IV1.1, March 97
SARPs Language: 				English

Summary of Defect: 

CPDLC SARPs require that both the latitude and longitude be specified when giving a position. Operationally it is required that only one or the other need to be supplied as in a clearance which says:  "CROSS 50W ...". This requirement has been agreed by ADSP as being a true operational requirement.

Assigned SME: 				Sub-Volume II SME

Proposed SARPs amendment: 

Modify CPDLC SARPs as follows:
Modify ASN.1 from: (Section 2.3.4.2.1)
	LatitudeLongitude ::= SEQUENCE
	{
	latitude		Latitude,
	longitude	Longitude
	} 
To:
	LatitudeLongitude ::= SEQUENCE
	{
	latitude		[0]	Latitude	OPTIONAL,
	longitude	[1]	Longitude	OPTIONAL
	} 

SME Recommendation to CCB: 	      -

CCB Decision:				CCB-2(Langen): SUBMITTED
					atnp_ccb_chair: ACCEPTED (22/09/97)
					atnp_ccb_chair: RESOLVED (20/10/97)