NOTICE ADVISORY TO NAVSTAR USERS (NANU) #050-90078
SUBJ: TENTATIVE GPS REPHASING SCHEDULE FOR 1990
1. CONDITION: PLANNED SATELLITE REPOSITIONING FOR 1990 IS INDICATED
IN PARA 2 BELOW. CHANGES TO GHESE PLANS MAY OCCUR WITHOUT NOTICE,
HOWEVER, USERS WILL CONTINUE TO BE NOTIFIED VIA THE NORMAL ADVISORY
MESSAGE (NANU) IMMEDIATELY PRIOR TO EACH EVENT. ACTUAL TIMES OF
OUTAGES WILL BE PROVIDED/UPDATED AS SPECIFIC INFORMATION BECOMES
AVAILABLE.
2. SATELLITE MAY BE UNUSABLE FOR UP TO 24 HOURS FOLLOWING INITIATE
AND TERMINATE TIMES:
A. PRN11 INIT 15 MAR 90 0355Z TERM 31 OCT 90
B. PRN 3 INIT 20 MAR 90 0804Z TERM 17 OCT 90
C. PRN13 INIT 23 MAR 90 0644Z TERM  3 OCT 90
D. PRN18 INIT  7 APR 90 1407Z TERM 24 NOV 90 AND 8 DEC 90
E. PRN19 INIT 12 APR 90 1138Z TERM 31 DEC 90
F. PRN 9 INIT 19 APR 90 1128Z TERM 19 APR 90
G. PRN16 INIT 26 APR 90 1517Z TERM 20 SEP 90
H. PRN 2 INIT  3 MAY 90       TERM  1 DEC 90
I. PRN14 INIT 13 MAY 90       TERM 10 NOV 90
J. PRN12 INIT 20 MAY 90       TERM 20 MAY 90
3. RECOMMENDATION: CONFIRM AVAILABILITY OF GPS SATELLITES PRIOR TO
USE.
4. POINT OF CONTACT: MAJ WILLIAM FAUVER AT COMMERCIAL (719)550-6379
OR AUTOVON 560-6379