ACE Weekly 08/16/02 - 08/22/02 All ACE spacecraft subsystems are performing nominally. No attitude maneuvers were executed this week. The next attitude maneuver is scheduled for 08/23/02. ============================================================================ OCRs Executed: None ============================================================================ Ongoing Activity: The engineering test to determine the new HGA constraint is continuing. The current constraint is 6.0 deg., with current tests reaching 6.5 degrees. The FOT has been monitoring the Signal Strength, the MFR AGC levels, and the Signal-to-Noise Ratios(SNR). The drop in RF levels from an HGA angle of 0 deg to 6 deg has been approximately 3dB. There has been no loss of telemetry due to the increased HGA angles. Analysis is ongoing to determine new HGA angle constraint. The following HGA angles and range values are from FDF. Man Date Pre Man Post Man Earth-ACE Range 03/28/02 -4.58 deg +4.38 1408287 km 04/04/02 -4.35 +4.50 1414808 04/11/01 -5.09 +3.79 1428491 04/18/02 -5.16 +3.85 1440512 04/26/02 -5.77 +5.56 1455949 05/06/02 -5.72 +5.43 1493008 05/17/02 -5.81 +5.31 1527979 05/28/02 -4.34 +4.88 1550263 06/06/02 -2.38 +5.96 1576064 06/20/02 -6.57 -3.66 1590405 06/26/02 -6.43 +5.94 1592458 07/12/02 -6.5 +6.5 1598879 07/30/02 -6.5 +6.5 1567441 08/13/02 -5.34 +6.43 1532343 ============================================================================ TPOCC Release 5.2 String 2 Testing Status Testing on String 2 has completed. Week 35 realtime operations will be transferred to String 2 (with String 1 as backup) to further confirm its operational capability. TPOCC Release 2 installation on String 1 is tentatively scheduled for September 4th. ============================================================================ Anomalies: DOY 02228 (08/16/2002)ACE Anomaly #G02-0098 LMC Problem at D16 From 14:52:12 to 14:58:12 and from 15:19:37 to 15:29:52 DSN Monitor Blocks were offline. D16 had to reboot the LMC and then Monitor Block data returned. IMPACT: No Monitor Block data for a total of 15 minutes. DOY 02228 (08/16/2002)ACE Anomaly #G02-0099 Downlink Format Command had to be retransmitted The first command in the procedure g_endday was retransmitted 4 times. This command is the Dnlk Fmt Cmd to Bin Dump. Station D16 and Ground System checks found no problems. FOT issued /Resume directive after 3 retransmits and the fourth command was accepted. IMPACT: None ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Glen A. Miller Honeywell Technology Solutions Inc. ACE Flight Operations Team Goddard Space Flight Center Building 14, Room W10A Mail Stop 428.2 Greenbelt, MD 20771 Office: 301-286-7071 Fax: 301-286-1729 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~