NOTICE ADVISORY TO NAVSTAR USERS (NANU) #039-91039 SUBJ: PRN6 UNUSABLE DAY 39 0701-0949 UTC 1. CONDITION ON DAY 39 (8 FEB 91): A. PRN9 (MCS: SVN6) USABLE OVER WESTERN NORTH AMERICA (WNA) AND PERSIAN GULF AREA (PGA). L-BAND-ON FORECAST FOR THE NEXT SEVEN DAYS: DAY DATE L-BAND-ON WNA L-BAND-ON PGA 39 08 FEB 91 39/0530-39/0730 39/1735-39/2000 40 09 FEB 91 40/0526-40/0726 40/1731-40/1956 41 10 FEB 91 41/0522-41/0722 41/1727-41/1952 42 11 FEB 91 42/0518-42/0718 42/1723-42/1948 43 12 FEB 91 43/0516-43/0714 43/1719-43/1944 44 13 FEB 91 44/0510-44/0710 44/1715-44/1940 45 14 FEB 91 45/0506-45/0706 45/1721-45/1936 B. PRN6 (MCS: SVN3) WAS UNUSABLE ON DAY 38 BEGINNING 0701 UTC UNTIL DAY 38 AT 0949 UTC. L-BAND WILL BE TURNED OFF BETWEEN 0745-1000 UTC UNTIL FURTHER NOTICE. 2. RECOMMENDATION: PRN6 WILL BE UNUSABLE FOR NAVIGATION OR POSITIONING DURING THESE OUTAGES. CONFIRM AVAILABILITY OF SATELLITES PRIOR TO USE. 3. POINT OF CONTACT: MAJ WILLIAM FAUVER AT COMMERCIAL (719)550-6379 OR AUTOVON 560-6379.