******************************************************************** UARS WEEKLY STATUS REPORT - 19 MAR 1999 ******************************************************************** *********** SOLSTICE *********** SOLSTICE continues to operate normally, collecting solar data on all available orbital tracking periods and stellar calibration observations, whenever possible. *********** SUSIM *********** SUSIM successfully performed a major calibration using all four deuterium lamps from March 12-15. As a part of this calibration SUSIM's lower spectrometer, for the first time, scaned the sun to provide additional and redundant calibration. At the same time, the elements in the working optical channel were replaced to provide more responsivity which should improve the noise characteristics of the solar UV irradiance data. With one exception, SUSIM gathered its normal solar, offset, and occultation data without apparent problems. On March 13, the primary long wavelength electrometer detector (PLE) entered a temporary condition which prevented its proper calibration and normal operation. This resulted in two lost scans. This abnormal behavior has not recurred during subsequent usage. No operations errors have been found that would explain this anomalous behavior. The cause remains under investigation. Reprocessing of the SUSIM data to data version 20 continues. *********** PEM *********** Nothing received. *********** HALOE *********** HALOE continues successful operations with all engineering parameters within nominal operating limits. Science data products are of excellent quality. *********** MLS *********** The instrument is now off as scheduled. MLS is scheduled to begin north viewing operations on Apr 4 and operate though Apr 10. *********** HRDI *********** Nothing received. *********** WINDII *********** WINDII reprocessing is under way, with Version V5_11 of the processing software. *********** MPG *********** Routine processing of instrument Daily Activity Plans continues with no problems. The MPG continues to assist the Project Scientist with the scheduling of instrument operations. *********** 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. 2 days CLA (7.0) ENG (L1-L3) (4R-2C-2F=2L) 49 days PEM (3.32) PROD (OA-L2) (760R-278C-1F=481L) 138 days SUS (7.0) PROD (668R-539C=129L) 131 days WIN (5.11) PROD (LOG) (2014R-131C=1883L) 13 days WIN (5.11) PROD (L1-L3) (2014R-13C=2001L) The CDHF is scheduled to participate in an End to End Y2K test on April 5th or April 19. This test will require a system clock time shift and an interruption to normal operations. Solstice excessive wallclock issue. No activity due to facilitiy priority activities. Target next week to run in debug! The CDHF has promoted WINDII V5.11 to production mode and started mission reprocessing. CDHF pending software upgrades: DEC AXP Fortran 6.5, DEC AXP OPEN VMS 6.2, OpenIngres. *********** FOT *********** This report covers 05 March 1999 (Orbit 40885, GMT Day 064) through 12 March 1999. 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 HRDI 065/0116 40887 Full Time HALOE 066/1212 40908 Off HALOE 066/1351 40909 On HALOE 069/0447 40948 Off HALOE 069/0627 40949 On HRDI 071/0006 40960 Day Only PEM 071/0314 40977 AXIS On The beta angle ranged between the angles of 46.2 degrees to 51.3 degrees for this report period. The beta angle is now decreasing toward a minimum angle of 0 degrees on 28 March 1999 (DOY 087). 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 0.9 to 1.3 degrees C. Additional battery performance data for each battery on 05 March 1999 and 12 March 1999 are provided in Appendix D. The clock error ranged from -10.8 to 11.4 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. % ALERTS = 00 % OUT-OF-LIMITS = 02 The following real-time command sheets were executed for the listed operational element(s) during this report period (see Appendix A). % FOT 04 % HALOE 04 % PEM 01 % SUSIM 01 UARS Anomaly Reports initiated during this report period are listed in Appendix E and summarized below. % FOT 03 One (1) Anomaly Report remained OPEN at the end of this report period (see Appendix E). TRANSPONDER FREQUENCIES: Transponder A: 99/054 - 2287.496948 Transponder B: 99/055 - 2287.498731 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 99/070 show the observatory data loss to be 22 hours, 46 minutes, 32.756 seconds (an increase of 00.000 seconds since last report period). This is a 0.0348 percent data loss which equals a 99.9652 percent data capture for the mission. The UARS Test and Training Simulator (UTTS) remains non-operational. The estimated time to repair the UTTS and return it to operation is unknown. OTHER SIGNIFICANT EVENTS UARS SATELLITE OPERATIONS The FOT continues to support the PEM team with diagnosis of the Energy Processor 6 status error. PEM EP6 is still not coming up nominally under PMON control. The FOT will conduct additional tests to identify where in the turn-on sequence the conflict occurs in the coming week. The FOT continues to investigate the feasibility of a new PMON action to change battery V/T curves based on loading to mitigate battery risks in sun pointing safehold. YEAR 2000 OPERABILITY SUPPORT - No change UARS PROPULSION MODULE B/D THRUSTER LINE FILL Planning continues for the simulator testing. UARS RE-ENGINEERING - TELEMETRY PROCESSING This task has been re-assigned as a part of the CSOC contract. FOT support is currently suspended. MEETINGS UARS supported the first Monthly Project Meeting held on 10 March 1999. Representatives from Central Data Handling Facility (CDHF), Flight Dynamics Facility (FDF), Flight Operations Team (FOT), Y2K testing, CSOC customer services and NASA GSFC (Project Scientist and Mission Director) were present. FUTURE SIGNIFICANT EVENTS The next UARS Yaw Around Maneuver (forward-to-reverse) is scheduled for 28 March 1999 (DOY 087). The spacecraft Roll attitude offset will be removed on DOY 075. PERSONNEL CHANGES None 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 12 March 1999 ORBIT AOS NO. SUBSYS REASON ----- --- --- ------ ------- 40893 065/1157 99-092 OBC Clk Adj fr 20.6 to 0.00 msec/day 40908 066/1212 99-094 HALOE Power OFF 40909 066/1351 99-095 HALOE Power ON 40918 067/0453 99-096 OBC Clk Adj fr 0.00 to 20.6 msec/day 40948 069/0447 99-097 HALOE Power OFF 40949 069/0627 99-098 HALOE Power ON 40965 070/0812 99-099 OBC Clk Adj fr 20.6 to 0.00 msec/day 40970 070/1551 99-100 SUSIM LOW GRATING 40977 071/0314 99-101 PEM "Power ON, AXIS " 40988 071/2058 99-102 OBC Clk Adj fr 0.00 to 20.6 msec/day _______________________________________________________________ APPENDIX B OUT-OF-LIMITS & ALERTS OCCURRENCES Week ending 12 March 1999 MNEMONIC STATE DESCRIPTION ORBITS --------- ----- ------------ ------ NBRECBI Y-HI NBTR B Current 40922,37,87 HATBAT Y-HI HALOE TBAT TMP 40939,78,80 The following ALERT occurrences were detected: MNEMONIC DESCRIPTION ORBITS --------- ------------ ------ None this report period _______________________________________________________________ APPENDIX C CLOCK & SOLAR ARRAY RATE CORRECTIONS Week ending 12 March 1999 CLOCK DRIFT RATE ADJUSTMENTS ORBIT TIME CLOCK RATE CHANGE ----- ---- ----------------- 40893 065/12:03 (06 Mar 99) from 20.6 to 00.0 msec/day 40918 067/04:57 (07 Mar 99) from 00.0 to 20.6 msec/day 40965 070/08:15 (11 Mar 99) from 20.6 to 00.0 msec/day 40988 071/21:07 (12 Mar 99) from 00.0 to 20.6 msec/day _______________________________________________________________ APPENDIX D UARS BATTERY PERFORMANCE DATA Week ending 12 March 1999 05 Mar 1999 - GMT Day 064 Beta = 46.2 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 -11.2/-33.6 -3.05/-4.62 +0.0/ +0.0 16.8 0.000 0.0 2 +22.4/-16.8 +5.15/+3.87 +28.0/-15.2 26.2 1.025 26.0 3 +39.2/-11.2 +3.87/+2.92 +27.2/-16.0 26.1 1.021 25.7 12 Mar 1999 - GMT Day 071 Beta = 51.3 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/-4.62 +0.0/ +0.0 16.8 0.000 0.0 2 +44.8/-5.6 +5.47/+4.51 +26.8/-15.6 25.0 1.022 20.8 3 +56.0/-5.6 +4.51/+3.23 +26.4/-16.0 25.0 1.022 20.6 V/T LEVEL CHANGES ORB# TIME LVL FR-TO ----- -------- ---------- no changes V/T 5 APPENDIX E UARS ANOMALY REPORTS Week ending 12 March 1999 NEW ANOMALY REPORTS GENERATED AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS ------ ------ ----- ---- --- ----------------- 99-011 FOT 40887 065/0306 14170 Generic Late Acquisition 99-011 FOT 40934 068/0624 14170 Generic Late Acquisition 99-011 FOT 40987 071/1846 14170 Generic Late Acquisition ANOMALY CLOSURE INFORMATION RECEIVED AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS ------ ------ ----- ---- --- ----------------- 99-006 FOT see list Feb 99 14170 Generic Late Acq ANOMALY INVESTIGATION REPORTS GENERATED AIR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS ------- ------ ----- ---- --- ----------------- None this report period OPEN ANOMALY REPORTS AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS ------ ------ ----- ---- --- ----------------- 99-011 FOT see list Mar 99 14170 Generic Late Acq SEVNTFW99/11