ACE Weekly 07/26/02 - 08/01/02 All ACE spacecraft subsystems are performing nominally. A nominal stationkeeping and attitude maneuver was executed on 07/30/02. The next attitude maneuver is scheduled for 08/13/02. ============================================================================ 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. Once all analysis has been completed, the new HGA constraint will be determined. 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 ============================================================================ TPOCC Release 5.2 String 2 Testing Status TPOCC Release 5.2 has been installed on String 2. FOT testing of String 2 will begin on August 5th. Target completion date is August 12th. ============================================================================ 26m Automation Demo Status Our analysis shows that there continues to be discrepancies in both the SFDU header information and the 5-16 DSN Monitor data. Many of the 5-16 DSN Monitor Parameters and SFDU Parameters have not been corrected since the previous 26m Automation tests done in Nov 2001 (including Signal/Noise Ratios). A second demo is scheduled for August 2nd. Following its completion, analysis will be performed to discern if the problems are specific to the demo or the release. ============================================================================ Anomalies: DOY 02213 (08/01/2002) - ACE Anomaly #S02-0019 SWICS PAPS 5V Yellow Low Limit Violation At 16:21:25 the SWICS Post Acceleration Power Supply 5V, mnemonic SSCPAP5V, flagged as a Yellow Low database limit violation at a value of 4.208 volts. It returned within database limits at 16:21:49 with a value of 4.736 volts. Notified Jim Raines. IMPACT: Unknown at this time. *********************************** Glen A. Miller Honeywell Technical Services Inc. ACE Flight Operations Team Goddard Space Flight Center Bldg. 14, Rm. W10A Mail Stop 428.2 Greenbelt, MD 20771 Office: 301-286-7071 Fax: 301-286-1729 ***********************************