******************************************************************** UARS WEEKLY STATUS REPORT - 05 MAY 2000 ******************************************************************** *********** SOLSTICE *********** We continue to gather enough data to meet all the SOLSTICE science objectives during this period of reduced tape recorder operations. SOLSTICE operates normally, collecting solar data on all available orbital tracking periods and stellar calibration observations whenever possible. Level 2 processing is halted due to bugs in the OA_SSPP_ATT service. CDHF and CSC personnel are working on the problem. *********** SUSIM *********** SUSIM continues to gather a near normal set of daily solar scans scheduled for periods of predicted telemetry. *********** ACRIM *********** Nothing received. *********** PEM *********** Nothing received. *********** HALOE *********** HALOE continues successful operations with all engineering parameters within nominal operating region. HALOE will be powered off some time May 7th as the spacecraft enters the graze period. *********** MLS *********** Nothing received. *********** HRDI *********** Nothing received. *********** WINDII *********** Nothing received. *********** MPG *********** The MPG participated in the Monthly Status Review Meeting, held on 3 May. The MPG distributed the Instrument Operations Schedule for the next yaw period: 4 June to 4 July 2000. All the systems in the MPG room were shutdown on May 4 for the power reconfiguration operation. All the systems are operational after reboot. Routine processing of instrument Daily Activity Plans continues with no problems. *********** CDHF *********** The CDHF processed current day data through level 3 for all active instruments. Additionally, CDHF personnel reprocessed: (R)= Requested (C) = Complete, (F)= Failed (L) = Days remaining to reprocess. - All requested reprocessing is complete as of this reporting period The CDHF will be sending out an updated version of the NASA Security Rules of Behavior to all users, in accordance with NASA ISO requirements. UARS CDHF REHOST: - Successful processing on Rehost System: Attitude Extraction, Observatory Log, Sensor Extraction, HALOE, MLS, SUSIM, Solstice, and WINDII. - An electronic ingest of LEVEL0, UARS DAY ,3144,3155,3156,3157,3158 was received from the LZP. Validation in progress. Sensor Extraction Software was processed for 3144. FDF has performed a successful quality check against the Sensor Files. - Test HRDI V4.4 on the Rehost System. - Preparing to test ISAMS V12.0 and PEM V3.32 software on the Rehost System. - Preparing to test DAAC transfer software. *********** FOT *********** REPORTING PERIOD This report covers 22 April, 2000 (Orbit 47073, GMT Day 113) through 28 April 2000 (Orbit 47177, GMT Day 119). SPACECRAFT OPERATION The observatory is now in Forward Flight (Southern Hemisphere viewing) and is performing nominally under two-battery operations. The instrument operational changes were: INSTRUMENT OPERATIONAL CHANGES Instrument Time Orbit Comment HALOE 113/0408 47075 Off HALOE 119/1152 47170 On HALOE 119/2130 47176 Off HALOE 119/2130 47176 On A Reverse-to-Forward Yaw Around maneuver (number 88) was successfully executed in Orbit 47127 beginning 116/15:52:58 and completing at 116/15:30:08 on 25 April 2000. The SSPP Instruments (ACRIM, SOLSTICE, SUSIM) were enabled as well as HRDI and PEM in day only operations. Due to the SA position at 269 degrees, the effective night length of the spacecraft after the maneuver was approximately 51 minutes. Post maneuver analysis of data indicate that during the Yaw Around, the end-of-night load bus voltage was 23.5 volts and the average depths of discharge (DODs) on Batteries 2 and 3 were approximately 22.0 and 22.5 percent respectively. The next (forward-to-reverse) YAW is scheduled for 05 June 2000 (DOY 157). The beta angle ranged between the angles of 17.7 degrees to 12.5 degrees for this report period. The beta angle is now increasing toward a maximum angle of +76.0 degrees on 15 May 2000 (DOY 136). Spacecraft battery 1, 2, and 3 performance monitoring continues. Battery 1 remains OFF the charge relay. Battery 2 and Battery 3 are currently maintaining greater than 23.8 V end-of-night (EON) load bus voltage. Battery temperatures are stable with a temperature delta between Battery 2 and Battery 3 of 1.0 to 1.3 degrees C. Additional battery performance data for each battery on 21 April 2000 and 28 April 2000 are provided in Appendix D. The clock error ranged from 3.4 to -9.8 msec during this report period. Clock rate adjustments are listed in Appendix C. All instrument and subsystem engineers were advised on the initial excursion of ALERTS or Out-Of-Limits conditions detected by the FOT for this report. A summary is listed below and the details of ALERT and Out-Of-Limits occurrences are listed in Appendix B. % OUT-OF-LIMITS = 07 % ALERTS = 01 The following real-time command sheets were executed for the listed operational element(s) during this report period (see Appendix A). % FOT = 06 % HALOE = 05 UARS Anomaly Reports initiated during this report period are listed in Appendix E and summarized below. % FOT = 03 Three (3) Anomaly Reports remained OPEN at the end of this report period (see Appendix E). TRANSPONDER FREQUENCIES: - Transponder A: 00/091 - 2287.496948 - Transponder B: 00/091 - 2287.499113 GROUND SYSTEM OPERATION Three (3) operational support problems occurred this period. Anomaly Reports are included in Appendix E. The data loss calculations supplied by Data Capture Facility (DCF) from mission start through UTC Day 00/118 show the observatory data loss to be 295 hours, 29 minutes, 41.209 seconds (an increase of 23 minutes 12.064 seconds since the last report period). The increase of 23 minutes 12.064 seconds occurred over one (1) day: - 23 minutes 12.064 seconds on Day 116 due to POCC scheduling error. These calculations have been recomputed to include 1999/346 through 2000/006 statistics using scheduled times. OTHER SIGNIFICANT EVENTS UARS SATELLITE OPERATIONS The FOT continues to have problems properly loading the new TMONs to the simulator. Both the FOT and its support staff are doing everything possible to identify and correct this problem so that the testing of the new safehold TMONs can begin. The FOT continues to develop an online procedure for safehold should it happen before the new TMONs are in place or during and OBC halt. This procedure has yet to be finalized and must undergo peer review before it will be ready. MEETINGS In support of the UARS Upgrade task, the FOT attended a meeting to discuss the basic roles and activities of each FOT member. The FOT held a meeting with NASA battery experts on 28 April 2000. The goal of the meeting was to determine the proper offset angle for the solar array in the new online procedure for safehold. Identifying this angle will require more analysis and will hopefully be determined sometime next week. FUTURE SIGNIFICANT EVENTS The next UARS Yaw slew is scheduled for June 05, 2000 (DOY 157). This maneuver will be a Forward to Reverse Flight maneuver (Northern Hemisphere viewing). Attachments: Appendix A, Real-time Commands Sheets Appendix B, Out-Of-Limits & ALERT Occurrences Appendix C, Clock & Solar Array Rate Corrections Appendix D, UARS Battery Performance Data Appendix E, UARS Anomaly Reports APPENDIX A REAL-TIME COMMAND SHEETS Week ending 28 April 2000 ORBIT AOS NO. SUBSYS REASON ----- --- --- ------ ------- 47074 113/0231 00-173 NBTR NBTR PLAYBACK 47075 113/0408 00-174 HALOE EARLY OFF- S/C LOW PWR 47075 113/0453 00-173 NBTR NBTR OPS DAY 113 47089 114/0314 00-175 NBTR NBTR PLAYBACK 47167 119/0749 00-176 NBTR NBTR OPS DAY 119 47170 119/1152 00-177 HALOE Power ON 47170 119/1249 00-178 OBC Clk Adj 0.00 to -20.6 msec/day 47174 119/1806 00-179 NBTR NBTR OPS DAY 120 47174 119/1837 00-180 HALOE Power ON 47176 119/2130 00-181 HALOE Power OFF 47176 119/2130 00-182 HALOE Power ON _______________________________________________________________________________ APPENDIX B OUT-OF-LIMITS & ALERTS OCCURRENCES Week ending 28 April 2000 The following Out-Of-Limits occurrences were detected: MNEMONIC STATE DESCRIPTION ORBITS --------- ----- ------------ ------ HRPSEQBIMON Y-HI PSE Quiet Bus Current Mon 47074 HRPSEQBIMON Y-HI PSE Quiet Bus Current Mon 47105-8 HRPTSPBIMON R-LO PTS Pulse Bus Current Mon 47117 HRPTSPBIMON R-LO PTS Pulse Bus Current Mon 47117-8 HRPSEQBIMON Y-HI PSE Quiet Bus Current Mon 47120-22 OBSVLBEON Y-LO Load Bus Volts at EON 47129 HRPTSPBIMON R-LO PTS Pulse Bus Current Mon 47135-8 The following ALERT occurrences were detected: MNEMONIC DESCRIPTION ORBITS --------- ------------ ------ OBSZ1OOL UFLTR Z1 Residual Exceeded 100 Arcsec 47127 APPENDIX C CLOCK & SOLAR ARRAY RATE CORRECTIONS Week ending 28 April 2000 CLOCK DRIFT RATE ADJUSTMENTS ORBIT TIME CLOCK RATE CHANGE ----- ---- ----------------- 47170 119/12:51 (28 Apr 00) from 0.00 to -20.6 msec/day _______________________________________________________________________________ APPENDIX D UARS BATTERY PERFORMANCE DATA Week ending 28 April 2000 21 April 2000 - GMT Day 112 Beta = 17.7 deg, SA Pos = 269 deg DIFF V (mV) TEMP (C) CURR (amp) EON V AVE C/D AVE BAT MAX/MIN MAX/MIN MAX/MIN MIN RATIO DOD(%) --- ----------- --------- ----------- ------ ------- ------ 1 -22.4/-44.8 -3.05/-4.31 +0.0/+0.0 15.8 0.000 0.0 2 +84.0/-5.6 +6.44/+5.15 +30.4/-14.4 24.0 1.030 22.5 3 +33.6/-44.8 +5.15/+3.87 +29.6/-15.2 23.8 1.030 22.0 28 April 2000 - GMT Day 119 Beta = 12.5 deg, SA Pos = 269 deg DIFF V (mV) TEMP (C) CURR (amp) EON V AVE C/D AVE BAT MAX/MIN MAX/MIN MAX/MIN MIN RATIO DOD(%) --- ----------- --------- ---------- ------- ------- ------ 1 -22.4/-44.8 -3.68/-4.94 +0.0/+0.0 15.8 0.000 0.0 2 +33.6/-11.2 +5.47/+3.87 +30.4/-14.4 24.3 1.022 20.5 3 +33.6/-5.6 +4.51/+2.60 +29.6/-15.2 24.2 1.020 20.1 V/T LEVEL CHANGES ORB# TIME LVL FR-TO ----- ----- ---------- no changes V/T 5 APPENDIX E UARS ANOMALY REPORTS Week ending 28 April 2000 NEW ANOMALY REPORTS GENERATED AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS ------ ------ ----- ---- --- ----------------- 00-016 FOT 47130 116/2012 22279 HGA slew error 00-018 FOT 47165 119/0415Z N/A AP-8 Crashed 00-019 FOT 47166 119/0635 N/A AP-8 Crashed ANOMALY CLOSURE INFORMATION RECEIVED AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS ------ ------ ----- ---- --- ----------------- 00-016 FOT 47130 116/2012 2227 HGA slew error 00-018 FOT 47165 119/0415Z N/A AP-8 Crashed 00-019 FOT 47166 119/0635 N/A AP-8 Crashed ANOMALY INVESTIGATION REPORTS GENERATED AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS ------ ------ ----- ---- --- ----------------- 00-002 FOT 47130 116/2012 22279 HGA slew error OPEN ANOMALY REPORTS AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS ------ ------ ----- ---- --- ----------------- 99-064 FOT 44135 10/8-9/99 N/A HRDI Cal Lamp Errors 99-071 FOT 44398 299/1212 21512 TPF Not Receiv 512 00-007 FOT see list April 00 14170 Generic Late Acq. SEVNTFW00/17