SUBJ: GPS STATUS 28 JAN 92
1. SATELLITES, PLANES AND CLOCKS (CS=CESIUM RB=RUBIDIUM):
A. BLOCK I : PRNS  3,  6, 11, 12, 13
   PLANE   : SLOT C4, A3, C3, A1, C1
   CLOCK   :      RB, RB, CS, CS, CS
B. BLOCK II: PRNS  2, 14, 15, 16, 17, 18, 19, 20, 21, 23, 24
   PLANE   : SLOT B3, E1, D2, E3, D3, F3, A4, B2, E2, E4, D1
   CLOCK   :      CS, CS, CS, CS, CS, CS, CS, CS, CS, CS, CS
2. CURRENT ADVISORIES (ADV) AND FORECASTS (FCST):
INFORMATION IS REPEATED FOR SEVEN DAYS AFTER EVENT CONCLUDES.
A. FORECASTS:
NANU      MSG DATE/TIME   PRN    TYPE  SUMMARY
121-91182 011354Z JUL 91  BLKII  FCST  SA ON    182/0400- UFN
007-92022 220149Z JAN 92  PRN21  FCST  SCHEDULED MAINTENANCE UPDATE
008-92033 221404Z JAN 92  PRN6   FCST  ECLIPSE OUTAGE SCHEDULE
B. ADVISORIES:
NANU      MSG DATE/TIME   PRN    TYPE  SUMMARY
009-92024 241440Z JAN 92  PRN13  ADV   024/0600-024/0614
3. REMARKS:
A. USERS OF GPS ARE CAUTIONED THAT THE SYSTEM IS NOT YET FULLY
OPERATIONAL. SIGNAL AVAILABILITY AND ACCURACY ARE SUBJECT TO
CHANGE DUE TO AN INCOMPLETE CONSTELLATION AND OPERATIONAL TEST
ACTIVITIES.
B. REF NANU 121 - SELECTIVE AVAILABILITY WAS REACTIVATED AT STANDARD
POSITIONING SERVICE ACCURACY LEVELS ON DAY 182 (01 JUL 91) AT 0400
UTC. VARIATIONS MAY BE SEEN IN THE EFFECT OF SA DURING TESTING, BUT
THE EFFECT SHOULD NOT EXCEED STANDARD POSITIONING SERVICE LEVELS.
THE POINT OF CONTACT IS MAJ ROB WORLEY (719)554-2634 OR DSN
692-2634.
C. REF NANU 008: PRN6 WILL BE SET UNAVAILABLE 30 MINUTES PRIOR TO
THE ECLIPSE TIMES LISTED BELOW AND SHOULD RETURN TO SERVICE WITHIN
FOUR TO SIX HOURS AFTER EXITING ECLIPSE DEPENDING ON THE CONDITION
OF THE VEHICLE. THE FOLLOWING IS A LIST OF PRN 6 ECLIPSE TIMES:
22 JAN 92 DAY 022 0536-0629 AND 1735-1828 UTC
23 JAN 92 DAY 023 0534-0626 AND 1733-1824 UTC
24 JAN 92 DAY 024 0532-0622 AND 1731-1820 UTC
25 JAN 92 DAY 025 0530-0619 AND 1729-1817 UTC => DAY 032 TO FOLLOW.
26 JAN 92 DAY 026 0528-0615 AND 1727-1813 UTC
27 JAN 92 DAY 027 0526-0611 AND 1726-1809 UTC
28 JAN 92 DAY 028 0525-0606 AND 1724-1804 UTC
29 JAN 92 DAY 029 0524-0602 AND 1723-1800 UTC
30 JAN 92 DAY 030 0523-0559 AND 1723-1755 UTC
31 JAN 92 DAY 031 0522-0552 AND 1722-1750 UTC
 1 FEB 92 DAY 032 0523-0547 AND 1723-1743 UTC
 2 FEB 92 DAY 033 0524-0539 AND 1727-1735 UTC
4. POINTS OF CONTACT:
A. CIVILIAN: US COAST GUARD AT COMMERCIAL (703)866-3806 VOICE OR
(703)866-3890 COMPUTER BBS.
B. MILITARY: 2SCS/DOAI 1LT INGEGNERI AT (719)550-6379 OR DSN 560-6379