NOTICE ADVISORY TO NAVSTAR USERS (NANU) 2025086 SUBJ: SVN80 (PRN01) UNUSABLE JDAY 348/1840 - JDAY 350/0700 1. NANU TYPE: UNUSABLE NANU NUMBER: 2025086 NANU DTG: 160701Z DEC 2025 REFERENCE NANU: 2025084 REF NANU DTG: 141843Z DEC 2025 SVN: 80 PRN: 01 START JDAY: 348 START TIME ZULU: 1840 START CALENDAR DATE: 14 DEC 2025 STOP JDAY: 350 STOP TIME ZULU: 0700 STOP CALENDAR DATE: 16 DEC 2025 2. CONDITION: GPS SATELLITE SVN80 (PRN01) WAS UNUSABLE ON JDAY 348 (14 DEC 2025) BEGINNING 1840 ZULU UNTIL JDAY 350 (16 DEC 2025) ENDING 0700 ZULU. 3. POC: CIVILIAN - NAVCEN AT 703-313-5900, HTTPS://WWW.NAVCEN.USCG.GOV MILITARY - GPS WARFIGHTER COLLABORATION CELL at HTTPS://GWCC-WS.CCE.AF.MIL/GPSOC, DSN 560-2541, COMM 719-567-2541, gpsoperationscenter@us.af.mil, HTTPS://GWCC-WS.CCE.AF.MIL MILITARY ALTERNATE - JOINT SPACE OPERATIONS CENTER, DSN 276-3526. COMM 805-606-3526. JSPOCCOMBATOPS@US.AF.MIL