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UARS WEEKLY STATUS REPORT - 27 Dec 2002
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SOLSTICE
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Nothing received.
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SUSIM
***********
Nothing received.
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ACRIM
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Nothing received.
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PEM
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Nothing received.
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HALOE
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Nothing received.
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MLS
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Nothing received.
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HRDI
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Nothing received.
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WINDII
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Nothing received.
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MPG
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The MPG continues to serve as the point-of-contact for UARS
instrument operations in support of the Science Traceability
Mission of UARS.
Daily processing of instrument Daily Activity Plans continues
with no problems.
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CDHF
***********
Nothing received.
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FOT
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REPORTING PERIOD
This report covers 14 December 2002 (Orbit 61571, GMT Day 348) through
20 December 2002 (Orbit 61676, GMT Day 354).
SPACECRAFT OPERATION
The observatory is now in Reverse Flight (Northern Hemisphere viewing)
and is performing nominally under two-battery operations. The
instrument operational changes were:
INSTRUMENT OPERATIONAL CHANGES
Instrument Time Orbit Comment
HALOE 348/2146 61585 POWER OFF
SOLSTICE 354/1316 61669 DAY ONLY TO FULL TIME
SUSIM 354/1458 61670 POWER ON
A Forward-to-Reverse Yaw Around maneuver (number 115) was successfully
executed in Orbit 61641 beginning 352/15:33:11Z and completing at
352/16:10:21Z on 18 December 2002. All instruments were in their off
or standby mode (including HRDI and PEM). Due to the SA position at
269 degrees, the effective night length of the spacecraft after the
maneuver was approximately 57.34 minutes. Post maneuver analysis of
data indicate that during the Yaw Around, the end-of-night load bus
voltage was 26.24 volts and the average depths of discharge (DODs) on
Batteries 2 and 3 were approximately 20.86 and 20.16 percent
respectively. The next (reverse-to-forward) YAW is scheduled for 27
January 2002 (DOY 027).
The beta angle ranged between the angles of 14.5 degrees to 05.2
degrees for this report period. The beta angle is now increasing
towards a maximum angle of 79 degrees on 08 January 2003 (DOY 008).
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 23.6 V end-of-night (EON) load bus
voltage. Battery temperatures are stable with a temperature delta
between Battery 2 and Battery 3 of 0.68 to 0.96 degrees C. Additional
battery performance data for each battery on 13 December and 20
December 2002 are provided in Appendix D.
The clock error ranged from -10.1 to -10.9 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 = 00
ALERTS = 00
The following real-time command sheets were executed for the listed
operational element(s) during this report period (see Appendix A).
FOT = 03
HALOE = 01
SOLSTICE = 01
SUSIM = 01
UARS Anomaly Reports initiated during this report period are listed in
Appendix E and summarized below.
FOT = 00
Two (2) Anomaly Reports remained OPEN at the end of this report period
(see Appendix E).
GROUND SYSTEM OPERATION
Zero (0) operational support problems occurred this period. Anomaly
Reports are included in Appendix E.
The data loss calculations are no longer being supplied by Data
Capture Facility (DCF).
OTHER SIGNIFICANT EVENTS
UARS SATELLITE OPERATIONS
The FOT successfully completed yet another yaw maneuver. As with all
maneuvers as of late, the FOT put UARS into a higher VT charging level
for one orbit before and remain at the higher VT level for one day
after the yaw to allow the batteries to recover.
The FOT continued testing the OBC image from the OBC crash with the
simulator this week. Nothing out of the ordinary has been seen yet to
date.
MEETINGS
-None this report period.
FUTURE SIGNIFICANT EVENTS
The next UARS Yaw slew is scheduled for 27 January 2003 (DOY 027).
This maneuver will be a Reverse to Forward Flight maneuver (Southern
Hemisphere viewing).
Attachments: Appendix A, Real-time Command 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 20 December 2002
ORBIT AOS NO. SUBSYS REASON
----- --- --- ------ ------
61585 348/2146 02-489 HALOE POWER OFF
61587 349/0116 02-490 OBC/CLK CLK ADJ FR -20.6 TO 0.0 MSEC/DAY
61640 352/1405 02-493 MACS YAW MANEUVER FWD TO REV
61656 353/1556 02-493 MPS BACK TO VT LEVEL-5
61659 353/2115 02-494 MPS BATSOC RESET
61669 354/1316 02-496 SOLSTICE DAY ONLY TO FULL TIME
61670 354/1458 02-497 SUSIM POWER ON - START
61671 354/1554 02-497 SUSIM POWER ON - CONTINUE
61673 354/1931 02-497 SUSIM POWER ON - COMPLETE
APPENDIX B
OUT-OF-LIMITS & ALERTS OCCURRENCES
Week ending 20 December 2002
The following Out-Of-Limits occurrences were detected:
MNEMONIC STATE DESCRIPTION ORBITS
-------- ----- ----------- ------
-None this report period.
The following ALERT occurrences were detected:
MNEMONIC DESCRIPTION ORBITS
-------- ----------- ------
-None this report period.
APPENDIX C
CLOCK & SOLAR ARRAY RATE CORRECTIONS
Week ending 20 December 2002
CLOCK DRIFT RATE ADJUSTMENTS
ORBIT TIME CLOCK RATE CHANGE
----- ----- -----------------
61587 349/0116 CLK ADJ FR -20.6 TO 0.0 MSEC/DAY
APPENDIX D
UARS BATTERY PERFORMANCE DATA
Week ending 20 December 2002
13 December 2002 - GMT Day 347 Beta = 16.5 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 -156.8/-179.2 -3.05/-4.31 +00.0/+00.0 08.3 0.000 0.0
2 +44.8/-22.4 +6.43/+5.14 +29.6/-14.8 24.2 1.030 22.0
3 +22.4/-50.4 +5.14/+3.87 +28.8/-15.2 24.2 1.020 21.7
20 December 2002 - GMT Day 354 Beta = 05.2 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 -156.8/-179.2 -3.68/-4.94 +00.0/+00.0 08.3 0.000 0.0
2 +16.8/-33.6 +5.14/+4.50 +29.6/-13.6 25.0 1.030 19.7
3 +28.0/-33.6 +3.87/+2.91 +28.4/-13.6 25.0 1.020 19.2
V/T LEVEL CHANGES
ORB# AOS TIME LVL FR-TO
----- -------- ---------
61640 352/1405 L5 -> L6
61656 353/1556 L6 -> L5
APPENDIX E
UARS ANOMALY REPORTS
Week ending 20 December 2002
NEW ANOMALY REPORTS GENERATED
AR NO. SUBSYS ORBIT TIME CDS PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
-None this report period.
ANOMALY CLOSURE INFORMATION RECEIVED
AR NO. SUBSYS ORBIT TIME CDS PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
02-061 FOT 61512 344/0124 31907 33 Second Data Dropout
ANOMALY INVESTIGATION REPORTS GENERATED
AIR NO. SUBSYS ORBIT TIME CDS PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
-None this report period.
OPEN ANOMALY REPORTS
AR NO. SUBSYS ORBIT TIME CDS PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
02-058 FOT 61113 317/1341 N/A NEG ACQ / UFLTR ERROR
02-060 FOT 61421 338/0057 N/A PSU Cmd Clock Timeout