ACE Weekly 12/17/2008 - 12/23/2008 All ACE spacecraft subsystems are performing nominally. ============================================================================ Orbit/Attitude: Type Attitude Date 12/19/2008 DOY 354 2008 Thrusters 2R 4R+ 4R- Duration 13:30 min Start 21:20:33z Stop 21:34:03z HGAStart -4.90deg HGAStop 7.70deg SunStart 8.83deg SunStop 7.60deg Nutation 0.09deg Firing 68 pulses FuelUsed 0.2227lbs FuelRemain 145.7836lbs FinalSCMass 1380.044lbs The next attitude maneuver is scheduled for Tuesday 12/30/2008. =========================================================================== OCRs: DOY 357 (12/22/2008) GND-196 Install Patchlink GSFC IT Security is requiring Patchlink software to be installed on RIONet computers. Patchlink was installed on acetlanpc, ac1taps1 and ac2sle2 on 12/22/2008. The remaining computers (ac2pc1, ac2taps2 and ac1sle1) will have Patchlink installed on 12/30/2008 after 1 week of operational testing. Only the ACE Windows and Linux computers are getting Patchlink; it will not be installed on the HP-UX 10 computers. Currently, the Patchlink daemon has been left running and the computers are automatically connecting to Patchlink server. The option to turn off the Patchlink daemon and re-enable it once a month is available if problems are found. ============================================================================ Activities: Data Capture: 100% DOY 356-363 2008 There is a higher than normal risk of data loss from October 2008 through February 2009. If there are problems with the passes, it may not be possible to acquire additional DSN time. This higher-risk period has been occurring every winter for the past couple of years. For more information refer to 10/14/2008 weekly. ============================================================================ Anomalies: DOY 352 12/17/2008 S-ACE-0396 G08-0129 DSS-46 TCP Configuration Both TCP channels were configured to send high-rate data to the ACE MOC (low latency). The FOT contacted the station to report duplicate data being sent to the MOC. DR#C106706. DSN is reviewing the desktop/TCP configuration. IMPACT: Minimal. The problem was resolved before the playback had started. Note that the ACE MOC software redumps duplicated playback data. If the problem was not resolved, the entire playback would have been redumped (2.5 hours). DOY 353 12/18/2008 S-ACE-0397 G08-0130 DSS-46 CMD/SLE Problems DSS-46 was unable to process SLE commands at Beginning Of Track (BOT). The station tried several troubleshooting efforts. The problem was resolved when the station unloaded and reloaded the desktop. DR#C106710 IMPACT: Activities delayed 20 minutes. DOY 354 12/19/2008 S-ACE-0398 G08-0131 DSS-46 CMD/SLE Problems DSS-46 was unable to process SLE commands at Beginning Of Track (BOT). The station tried several troubleshooting efforts. The problem was resolved when the station switched from TCP1 to TCP2 and then back to TCP1. DR#C106711 IMPACT: Activities delayed 33 minutes. DOY 350 12/15/2008 S-ACE-0399 G08-0132 TPOCC History File Problem TPOCC did not write playback data to the A4 history file, but did write the data to the AB history file. This is a Known TPOCC Issue (#6 of 23 documented issues). This last occurred 03/04/2004 (AR#G04-0019). IMPACT: Minimal. This problem causes a little bit of confusion when it occurs due to the conflicting data files and the fact that it hasn't occurred for 4 years. DOY 357 12/22/2008 S-ACE-0400 G08-0133 AC2SLE2 unable to connect to DSS-27 The backup ACE MOC SLE software (ac2sle2) was used in preparation for the Patchlink software install (OCR GND-196). However, ac2sle2 was not able to connect to DSS-27. The problem was due to a DSS-27 IP address change made on Friday 08/29/2008 for a DSN test (SPS TTC PIT). The ACE MOC SLE software (ac2sle2) configuration file was not restored after the DSN test was completed. IMPACT: Minimal. Operations was switched back to ac1sle1 and the Patchlink install occurred on ac2sle2. The ac2sle2 configuration file was restored and used for operations with Patchlink on DOY 358. ac1sle1 remains available without Patchlink if problems occur with ac2sle2. DOY 357 12/22/2008 S-ACE-0401 G08-0134 DSS-27 Antenna Pointing Problems The DSS-27 antenna kept going off-point. At 16:51:25, the antenna should have been at AZ:135 EL:23, but was instead at AZ:58 EL:23. This occurred again at 18:06:24 and 18:15:16. DSS-27 requested to not restore the uplink for the remainder of the support (1820-1845z, 25 minutes). No further antenna pointing problems occurred. DR#G109109 IMPACT: Minimal. All playback data was captured. Final state-of-health checks were not performed.