NOTICE ADVISORY TO NAVSTAR USERS (NANU) #092-93103 SUBJ: PRN31 USABLE 103/2053 UTC 1. CONDITION: PRN31 (SVN31) WAS SET USABLE ON DAY 103 (13 APR 93) AT 2053 UTC. PRN31 RESIDES IN THE C3 SLOT. 2. 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. 3. POC: CAPT SKINNER AT COMMERCIAL (719) 550-6378 OR DSN 560-6378.