ACE Weekly 09/19/03 - 09/25/03 All ACE spacecraft subsystems are performing nominally. An attitude maneuver (Dog-Leg) was successfully executed on 09/24/03. The next attitude maneuver is scheduled for 10/03/03. The 09/19/03 (DOY 262) pass was canceled due to Hurricane Isabel. All data was retrieved during the subsequent passes. ============================================================================ Orbit Events: ACE completed the SEV transit 09/23/03. The minimum SEV angle was 1.76 degrees. The essential timeline based on a 30-min step scan for this 22 day, 8.5 hour event was: - SEZ entry (4.75 deg inbound) on Sept. 1 at 0100Z - Minimum Sun-Earth-ACE angle = 1.760 deg on Sept. 12 at 0800Z - SEZ exit (4.75 deg outbound) on Sept. 23 at 0930Z No problems were encountered during this transit. Next SEV transit will occur November 26th through December 20th. The minimum SEV angle expected will be approximately 1.19 degrees. ===================================================================== OCRs Executed: NONE ===================================================================== Ongoing Activities: TAPS: Trending, Analysis and Plotting System (TAPS) development continues with emphasis being placed on fixing the DRs attributed to prior releases. Release 4.1.7 was successfully installed on 09/09/03. A list of priority DRs has been submitted to SGT in order to focus attention on those requirements the FOT determined critical to transition. The final Release 4.1.8 date is TBD. ---------------------------------------------------------------------------- Automation (ROBOTT): - Offline testing on String 1 is progressing well. Individual button testing is complete and "Start Pre/Post Pass" button testing is going well. CRON testing will begin 09/30/03 and run through 10/07/03. - R/T operations is planned to move back to String 1 on 10/07/03 if testing is successful. - Automation Team testing of HSM and Command & Control on String 3 continues. C&C is shadowing passes and an expected delivery date to the FOT is early October. - The first draft of the SUG is expected to completed by 10/01/03. ===================================================================== Anomalies: DOY 03263 (09/20/2003) ACE Anomaly G03-0086 - GDS (DSS-27) Degraded Data / Line Problems At 2005, the FOT started receiving degraded data. DSS-27 was notified but stated everything appeared fine. However, they did state that technicians were working on the communications lines at the time. At 2010, data was nominal. JPL Comm was notified of the degraded data and stated the cause as line problems. IMPACT: Degraded data realtime however all data was recovered via CDR File. DR# N101418 DOY 03268 (09/25/2003) ACE Anomaly G03-0087 - DSN - Corrupted Data from DTF-21 FOT noticed frames with the wrong Spacecraft ID and frequent VC2 sequence errors within the telemetry. FOT notified DSS-16 and asked if they saw anything on their end regarding the telemetry. DSS-16 informed us of no problems seen on their end. FOT determined that DTF-21 data was online. FOT notified JPL Comm of the situation and requested they halt the transmission of the bad data. IMPACT: Corrupted telemetry from 1654 - 1713. Clock calibration corrupted. No Clock calibration files delivered to ACE Science Center for DOY 03268 - 03269 . Telemetry recovered via CDR File. DR # N101443 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Glen A. Miller ACE Flight Operations Observatory Engineer Honeywell Technology Solutions Inc. Goddard Space Flight Center Building 14, Room W10A Mail Stop 428.2 Greenbelt, MD 20771 Office: 301-286-7071 Pager: 800-425-3174 Fax: 301-286-1729 Email: gamiller@pop500.gsfc.nasa.gov ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~