ACE Weekly 02/03/05 - 02/10/05 All ACE spacecraft subsystems are performing nominally. ============================================================================ Orbit/Attitude: No maneuvers were executed this reporting period. The next attitude maneuver is scheduled for Friday 02/11/05. ============================================================================ OCRs: SEP-109 Planned for next week Update the 2kVC setpoint to correspond to the current Fan 3 pressure. ============================================================================ Ongoing Activities: The Sun-Earth-Vehicle (SEV) angle will reach 1.435 deg on 02/21/05 (from FDF). DSN has had no problems acquiring the downlink for SEV angles greater than 1 deg. No problems are expected with the expanding Lissajous orbit. The requirements review for SLE (Space Link Extension) implementation of ACE commanding to DSN is underway. ============================================================================ Extra Activities: DOY 040 (02/09/05) IPNoc Router upgrade completed with only a couple of ~2 minute TLM outages. All data captured on CDR. ============================================================================ Anomalies: DOY 035 (02/04/05) ACE Anomaly S05-0007 SEPICA Fan 3 Pressure Drop At 11:18:38z SSSPC3P began to lose pressure. Yellow Low limit (raw=300) violated at 11:20:38z. Red Low limit (raw=245) violated at 11:29:39z. SSSPC3P reached zero at 13:20:42z. As a result of the pressure drop, SSS2KCV, SSS2KI and SSS2KV were turned off at 11:42:15z. SSSALARMS transitioned from 6 to 14 at 11:42:51z. IMPACT: (from Mark Popecki) The Fan 3 pressure is now low, and the fan 3 anode voltage has been turned off by a pressure sensor. It may remain in this state permanently, or the valve may open on its own, as it did in 1998.