SUBJ: GPS STATUS 03 MAY 90 1. SATELLITES, PLANES AND CLOCKS (CS=CESIUM RB=RUBIDIUM): SLOTS MAY NOT BE FINAL UNTIL AFTER 21-SATELLITE REPHASING A. BLOCK I : PRNS 3, 6, 9, 11, 12, 13 PLANE : SLOT D1, A3, A2, C2, A1, C1 CLOCK : RB, RB, RB, CS, CS, CS B. BLOCK II: PRNS 2, 14, 16, 17, 18, 19, 20 PLANE : SLOT B2, E1, D2, F2, F3, A4, B3 CLOCK : CS, CS, RB, CS, CS, CS, CS 2. CURRENT ADVISORIES (ADV) AND FORECASTS (FCST): INFORMATION IS REPEATED FOR SEVEN DAYS AFTER EVENT CONCLUDES NANU MSG DATE/TIME PRN TYPE SUMMARY 085-90115 250100Z APR 90 PRN6 ADV UNUSABLE 114/220-114/2212 086-90115 251630Z APR 90 PRN3 ADV UNUSABLE 115/1408-115/1419 087-90119 292350Z APR 90 PRN11 ADV UNUSABLE 119/2207-119/2220 088-90120 300550Z APR 90 PRN11 ADV UNUSABLE 120/0424-120/0515 089-90122 022124Z MAY 90 PRN10& FCST UNUSABLE 128/0800-128/1700 PRN18 & 130/0800-130/1700 090-90122 022126Z MAY 90 PRN2& CHANGE TO REPHASING PLAN PRN14& PRN12 3. REMARKS: A. THE CURRENT GPS CONSTELLATION BEGAN BROADCASTING NAVIGATION MESSAGES AT ACCURACY LEVELS CONSISTENT WITH STANDARD POSITIONING SERVICE ON 25 MAR 90. GPS IS NOT EXPECTED TO BE DECLARED FULLY OPERATIONAL UNTIL 1993. ANY GPS USERS ARE OPERATING AT THEIR OWN RISK. 4. SATELLITE REPOSITIONING: PRN INITIATE TERMINATE#1 TERMINATE#2 UNUSABLE (DAY/UTC) 11 15 MAR 90 31 OCT 90 74/0335-75/0225 ACTUAL 3 20 MAR 90 17 OCT 90 79/0700-79/1220 ACTUAL 13 29 MAR 90 3 OCT 90 88/0142-88/1105 ACTUAL 18 7 APR 90 24 NOV 90 8 DEC 90 97/0318-97/1902 ACTUAL 19 11 APR 90 101/0421-101/0634 RESCHD 19 12 APR 90 31 DEC 90 102/0440-102/1411 ACTUAL 9 19 APR 90 19 APR 90 109/2126-110/2126 RESCHD 9 21 APR 90 21 APR 90 111/1035-111/1440 ACTUAL 16 26 APR 90 20 SEP 90 116/0736-116/1509 ACTUAL 2 3 MAY 90 1 DEC 90 123/1933-124/1933 FORECAST 14 14 MAY 90 10 NOV 90 134/0136-135/0136 FORECAST 12 20 MAY 90 21 MAY 90 140/2056-141/2056 FORECAST 5. POINT OF CONTACT: MAJ FAUVER AT (719)550-6379.