8/15/19 3/15/07 1/30/20 AIM  7110.65R CHG 2 AIM TBL 5 − 3 − 6 Crossing Constraint Message Elements (CSTU) TBL 5 − 3 − 7 Air Traffic Advisory Uplink Message Elements CPDLC Message Sets Operational Definition in PANS − ATM (Doc 4444) FANS 1/A ATN B1 Response Message  Element  Identifier Message Element Intended Use Format for  Message Element Display UM154 RADAR SERVICES TERMI- NATED N/A R ADVU − 2 Advisory that the ATS surveillance service is terminat- ed. SURVEILLANCE SERVICE TERMI- NATED CPDLC Message Sets Operational Definition in PANS − ATM (Doc 4444) FANS 1/A ATN B1 Response Message  Element  Identifier Message Element Intended Use Format for  Message Element Display UM49 CROSS ( posi- tion ) AT AND MAIN- TAIN ( altitude ) Note 1.  −  A vertical range cannot be pro- vided. Note 2.  −  This mes- sage element is equiv- alent to CSTU − 1 plus LVLU − 5 in Doc 4444. N/A W/U CSTU − 1 Instruction that the specified position is to be crossed at the specified level or within the speci- fied vertical range. CROSS  (position) AT  (level) UM61 CROSS  (posi- tion)  AT AND MAIN- TAIN  (altitude)  AT (speed) Note 1.  −  A vertical range cannot be pro- vided. Note 2.  −  This mes- sage element is equiv- alent to CSTU − 14 plus LVLU − 5 in Doc 4444. UM61 CROSS (position)  AT AND MAINTAIN  (level) AT  (speed) W/U 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) En Route Procedures 5 − 3 − 6