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.

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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.

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OCRs Executed:

NONE

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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.

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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.

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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
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~