ACE Weekly 04/22/2009 - 04/28/2009 All ACE spacecraft subsystems are performing nominally. ======================================================================== Orbit/Attitude: No maneuvers were completed this week. The next attitude maneuver is scheduled for Friday 05/01/2009. ======================================================================= OCRs: None ======================================================================== Activities: Data Capture: 100% DOY 109-116 2009 The ASC address for receiving real-time data changed on April 14. The request for updating the GSFC fanout continues to work through the NISN/Nascom system. ASC (ACE Science Center) has not received real-time data since April 14. ======================================================================== Anomalies: DOY 111 04/21/2009 S-ACE-0431 G09-0026 DSS-46 Transmitter Failures DSS-46 transmitter failure (TXR1 S20K) at Beginning Of Track ("body coolant indication"). The station switched to backup transmitter (TXR2 S2K) within 10 minutes. In the last hour of the pass, the transmitter (TXR S2K) tripped off ("Klystron drive power high fault"). The problem was resolved within 40 minutes. DR#C106879 and C106880 IMPACT: Spacecraft bin dumps were being performed during the final transmitter failure. TPOCC did not successfully write the dump file; the procedure did not complete and the rest of the state-of-health checks were not performed. Final state-of-health checks were performed on the following pass. DOY 113 04/23/2009 S-ACE-0432 G09-0027 DSS-27 Red DSN has declared DSS-27 red for 2 weeks (DOY 113-128). 9 out of 15 ACE passes during this time were scheduled with DSS-27. The SSMO scheduling team has done a wonderful job of rescheduling passes. DR#G109389 IMPACT: There were no passes on DOY 113 or DOY 116. Passes have been moved to avoid SSR Failovers (SSR capacity 43 hours). Data capture continues to be 100%. Background Information. ACE playback is initiated via ground command (as opposed to spacecraft load). This gives ACE considerable flexibility in moving automated passes. The ACE Mission Director was the driving force behind this design. DOY 114 04/24/2009 S-ACE-0433 G09-0028 DSS-24 Power Outage Goldstone power outage caused tracking to stop with DSS-24 (1657z). Telemetry and Commanding restored after 1 hour (1756z) but with only 25 minutes left in the pass. DR#G109390 IMPACT: SSR redumps and final state-of-health checks were performed on the following pass. DOY 115 04/25/2009 S-ACE-0434 G09-0029 DSS-46 CMD/SLE Problems DSS-46 was unable to process SLE commands at Beginning Of Track (BOT). The Ops Chief notified the FOT (Saturday). Rebooting the TCP resolved the problem. The last DSS-46 CMD/SLE problem occurred on 02/19/2009. DR#C106892 IMPACT: Activities delayed 20 minutes.