ACE Weekly 08/01/03 - 08/07/03

All ACE spacecraft subsystems are performing nominally. An attitude 
maneuver was successfully executed on 08/07/03. The next attitude maneuver 
is scheduled for 08/18/03.

============================================================================
Orbit Events:

The next SEV transit will occur during the 09/01/03 - 09/23/03 time frame. 
Expected minimum SEV angle will be 1.76 degrees.

The essential timeline based on a 30-min step scan for this 22 day, 8.5 
hour event is:
- 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

============================================================================
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 4.1.6 was installed successfully on 08/05/03 and is 
currently in test by FOT.

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Automation (ROBOTT):
FOT testing of ROBOTT Release 0.1 is ongoing. CRON testing on String 2 is 
progressing, although some minor problems have occurred.

Command & Control (C&C) ES still in development phase. Testing results and 
corrections still need to be made. Expected development testing by the 
Automation Team to resume at the end of August.

FOT testing of the latest OFFLINE release on String 3 is progressing and 
should be completed in time for the install of OFFLINE on String 2 next 
Thursday (14 Aug 03).

============================================================================
Anomalies:

DOY 03215 (08/03/2003) - ACE Anomaly G03-0069 - MAD 26m (DSS-66) TCP 
Swap/Reboot
Data was offline from 14:33:07 through 14:34:04 and from 14:37:31 through 
14:45:51.  Contacted DSS-66, after the first telemetry dropout swapped from 
Telemetry Control Processor (TCP) 1 to TCP 2.  After the second telemetry 
dropout, rebooted TCP 1 then swapped from TCP 2 back to TCP 1.  No further 
problems seen during the pass.  IMPACT:  None.  All data was 
recovered.  DR# M101792

DOY 03217 (08/05/2003) - ACE Anomaly S03-0016 - Mnemonic SSCPAM5V Red High 
Limit Violation
At 18:28:36 SSCPAM5V violated the red high limit of -4.5V, at a value of 
-4.49.  It returned within limits at 18:29:13.  Notified J. 
Raines.  IMPACT: Unknown.  FOT will continue to monitor.

DOY 03219 (08/07/2003) - ACE Anomaly G03-0070 - GDS 26m (DSS-16)  No 
Tracking Data
At 13:05, DSS-16 reported errors with the tracking data.  The station 
stated they will need to drop their carrier and reboot the MPA (Metric 
Pointing Assembly).  At 13:12, the FOT gave DSS-16 a go to take down the 
carrier and reboot the MPA.  DSS-16 estimated it would take 10 minutes to 
reboot the MPA.  At 13:15:20, telemetry went offline.  At 13:29, DSS-16 
stated the reboot was complete but the errors remained.  Telemetry was back 
online at 13:33:53.  The station asked the FOT if they would to attempt 
another reboot of the MPA.  After consulting FDF, the FOT decided against 
another reboot and continued with the pass without tracking data.  At 
13:37, the FOT gave DSS-16 a go to bring carrier up.  At 13:39, the FOT 
received the go for command and confirmed a good command link with a 
/NO_OP.  IMPACT:   Loss ability to command from 13:12 to 13:43.  No 
tracking data for entire pass.  All telemetry was eventually 
recovered.  DR# G103147

DOY 03219 (08/07/2003) - ACE Anomaly G03-0071 - GDS 26m (DSS-16)  Antenna 
Stopped
At 15:16:09 telemetry dropped out.  DSS-16 stated that their antenna had 
'stopped'.  Telemetry lost again at 16:59:50 due to the same 
problem.  IMPACT:  About 6 minutes of telemetry was lost for both 
outages.  All data was recovered in redumps of the SSR.  DR# G103154

DOY 03219 (8/07/2003) - ACE Anomaly G03-0072 - GDS 26m (DSS-16) TCP reboot
Telemetry dropped out at 15:23:29.  DSS-16 stated that both their TCP's had 
'halted'.  DSS-16 rebooted the TCP's and telemetry was back online at 
15:29:58.  A /NO_OP commands was sent to verify a good command 
link.  IMPACT:  About 6 minutes of telemetry loss.  All data was recovered 
in playbacks of the SSR.  DR# G103155

DOY 03219 (08/07/2003) - ACE Anomaly G03-0072 - GDS 26m (DSS-16) Monitor 
Blocks Offline
 From 15:25 to 15:44 DSN monitor blocks were offline.  DSS-16 swapped their 
RNS and SCP systems.  IMPACT:  No Monitor data for 20 minutes.  DR# G103156

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