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UARS WEEKLY STATUS REPORT - 03 DEC 1999
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SOLSTICE
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SOLSTICE continues to operate normally, collecting solar data on all
available orbital tracking periods and stellar calibration observations,
whenever possible.
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SUSIM
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In spite of continuing telemetry outages, the SUSIM was scheduled this
past week for a normal set of solar scans. Although these were
apparently successful, only about 75% of the data were retrieved.
Potentially, this could raised to 100% if the times of telemetry
availability are known at the time when SUSIM's plans are written.
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ACRIM
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Nothing received.
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PEM
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The PEM/AXIS was operated from November 22 through November 28. During
this time, AXIS computed energy deposition from electrons which were derived
from the measured X-ray spectrum. All 16 of the AXIS pixels were active.
The PEM spectrometers continue to be active under PMON control*. While
under PMON control, the PEM spectrometers computed energy deposition from
electrons and protons measured in-situ by the particle spectrometers.
*Beginning of power orbit day (PEM activation): array current >5 amps, array
voltage >53.5 volts, and battery current >2.0 amps.
End of power orbit day (PEM deactivation): time in power orbit day >4 minutes,
array current <9 amps, and battery currents <0.2 amps.
Power orbit day variation: ~39-40 min at yaw to ~50-51 min at maximum beta.
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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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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. The
schedule of planned instrument operations for the next yaw
cycle (8 December 1999 to 6 January 2000) was distributed.
The MPG has continued to assist the FOT with analysis of the
current tape recorder anomaly (NBTR B) and its impact on
science data collection.
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CDHF
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The CDHF continues to notify all PI Software Representatives when Data Gaps
occur in the LEVEL0 data due to the UARS Spacecraft Anomaly.
The CDHF notified all PI Software Representatives regarding the re-ingest of
UARS DAY 2998 Version 3 for better quality and more data. Appropriate
production reprocessing was done against the Version 3 data.
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.
18 days CLA (7.0) PROD (L1-L3) (476R-418C-21F=37L)
15 days GPI (4.05) PROD (CLAES L3B) (372R-332C-2F=38L)
41 days WIN (5.11A) PROD (L1-L3) (520R-60C-4F=456L)
UARS CDHF REHOST:
- Testing SUSIM V7.1 on the Rehost System.
- Preparing to test SOLSTICE V4.62 on the Rehost
System.
- Rehost procedures continued to be developed and/or reviewed.
- Migration for all data levels continued.
CDHF pending software upgrades: none
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FOT
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REPORTING PERIOD
This report covers 20 November, 1999 (Orbit 44765, GMT Day 324) through 26
November 1999 (Orbit 44869, GMT Day 330).
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
WINDII 326/0046 44795 On
PEM 326/1214 44802 AXIS On
HALOE 329/1714 44850 On
WINDII 330/2312 44869 Off
The beta angle ranged between the angles of 74.9 degrees to 50.3 degrees for
this report period. The beta angle is now decreasing toward a minimum angle of
-2.0 degrees on 08 December 1999 (DOY 342).
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 19 November 1999 and 26 November 1999 are provided in Appendix D.
The clock error ranged from -11.4 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 = 11
The following real-time command sheets were executed for the listed operational
element(s) during this report period (see Appendix A).
% FOT = 07
% HRDI = 03
% WINDII = 02
% PEM = 01
% HALOE = 01
UARS Anomaly Reports initiated during this report period are listed in Appendix
E and summarized below.
% FOT = 02
Three (3) Anomaly Reports remained OPEN at the end of this report period (see
Appendix E).
TRANSPONDER FREQUENCIES:
% Transponder A: 99/284 - 2287.496981
% Transponder B: 99/265 - 2287.498700
GROUND SYSTEM OPERATION
Two (2) 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 99/329 show the observatory data loss to be 185 hours, 19
minutes, 46.873 seconds (an increase of 34 hours 22 minutes 56.768 seconds
since the last report period). This is a 0.2587 percent data loss which equals
a 99.7413 percent data capture for the mission.
The increase of 34 hours 22 minutes 56.768 seconds occurred over seven (7)
days:
7 00 hours 03 minutes 16.192 seconds on Day 323 due to a S/C TR problem.
7 00 hours 01 minutes 45.312 seconds on Day 324 due to a S/C TR problem.
7 00 hours 02 minutes 37.312 seconds on Day 325 due to a S/C TR problem.
7 05 hours 50 minutes 16.000 seconds on Day 326 due to a S/C TR problem.
7 11 hours 25 minutes 45.824 seconds on Day 327 due to a S/C TR problem.
7 08 hours 37 minutes 29.120 seconds on Day 328 due to a S/C TR problem.
7 08 hours 22 minutes 47.008 seconds on Day 329 due to a S/C TR problem.
OTHER SIGNIFICANT EVENTS
UARS SATELLITE OPERATIONS
NBTR B anomalies continued again on Monday, Nov. 22, 1999. By Tuesday morning
all PASS 1 data was non recoverable. NBTR B operation continued throughout the
week with only PASS 2 data captured. Real-time supports were increased to
compensate for the lost PASS 1 data. The current plan for NBTR B operations
are the following:
* Resume maximum coverage with a combination of TDRSS SSA and MA supports.
* Continue NBTR B anomaly testing and analysis.
* Continue NBTR B operations in 4-Mux mode.
* Coordinate real-time supports with PASS 2 coverage.
* Determine if PASS 2 and real-time operations can fulfill mission objectives.
Currently only 56 to 62 minutes in a 96 minute orbit possible for real-time
operations.
* Review possibility of modification to UARS flight software and ground system
to accept three TDRSS inputs to provide maximum orbital coverage.
* Review science priorities with acquisition strategy to maximize science
return. Initial science assessment by mid December. Final science review in
early January.
The Flight Operations Team completed the ERASE command test on Tuesday, Nov.
23, 1999. A /RAW command was used to send the Serial Magnitude command that
was identified to the FOT to turn ERASE on. The FOT initiated this command in
two forms, wind and erase as two separate commands and as a composite command.
The ERASE function did not activate in either test scenario. To ensure that
the ERASE did not activate even though telemetry showed the contrary, PASS 2
was recorded, dumped and evaluated. The PASS 2 data evaluated from this test
was determined to be non-recoverable.
YEAR 2000 OPERABILITY SUPPORT
All areas identified to or by the Flight Operations Team for Y2K testing have
been completed. There are no other areas identified at this time that have not
been Y2K certified.
MEETINGS
No relevant meetings this week.
FUTURE SIGNIFICANT EVENTS
No specific date was agreed upon for UARS Safehold configuration discussions.
Instead, the Supporting Engineers involved will be contacted every two weeks to
determine if either the Flight Operations Team or Supporting Engineers have any
new developments that should be discussed in a group. It is expected that one
more meeting will be held before Y2k as an update to UARS safehold expectations
for the new century.
UARS has tested and prepared for the Year 2000 event. Special considerations
have been made in preparation for a non nominal 1999 to 2000 transition.
The next UARS Yaw slew is scheduled for December 8, 1999. This maneuver will
be a Reverse to Forward Flight maneuver(Southern 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 26 November 1999
ORBIT AOS NO. SUBSYS REASON
----- --- --- ------ -------
44775 324/1610 99-388 HRDI SAFEHOLD DUE TO HIGH BARREL TEMP
44788 325/1240 99-389 HRDI SAFEHOLD DUE TO HIGH BARREL TEMP
44795 326/0046 99-390 WINDII POWER ON
44800 326/0734 99-377 HRDI SAFEHOLD DUE TO HIGH BARREL TEMP
44802 326/1214 99-391 OBC CLK ADJ. 41.2 to 20.6 MSEC/DAY
44802 326/1214 99-392 PEM AXIS ON
44809 326/2221 99-393 TMON DISA TMON 37 RPT
44821 327/1713 99-394 NBTR NBTR SPOOLING
44822 327/1858 99-395 NBTR NBTR FFWD ERASE
44825 328/0048 99-396 OBC TRANSMITTER NOOPS
44835 328/1627 99-397 OBC CLK ADJ. 20.6 to 41.2 MSEC/DAY
44850 329/1714 99-398 HALOE POWER ON
44858 330/0557 99-399 OBC CLK ADJ. 41.2 to 20.6 MSEC/DAY
44869 330/2312 99-400 WINDII POWER OFF
__________________________________________________________________________
APPENDIX B
OUT-OF-LIMITS & ALERTS OCCURRENCES
Week ending 26 November 1999
The following Out-Of-Limits occurrences were detected:
MNEMONIC STATE DESCRIPTION ORBITS
--------- ----- ------------ ------
HRPTSBARTMP R-LO HRDI TELESCOPE BARREL TEMP 44768-75
HRPTSBARTMP Y-LO HRDI TELESCOPE BARREL TEMP 44776-7
HRPTSBARTMP Y-LO HRDI TELESCOPE BARREL TEMP 44783-86,89
HRPTSBARTMP R-LO HRDI TELESCOPE BARREL TEMP 44787-89
QTZEPSIF1 Y-LO ZEPS I/F PLATE AFT 44789-91
HRPTSBARTMP Y-LO HRDI TELESCOPE BARREL TEMP 44797,801
HRPTSBARTMP R-LO HRDI TELESCOPE BARREL TEMP 44798-800
HRPTSBARTMP Y-LO HRDI TELESCOPE BARREL TEMP 44815-24
HRPTSBARTMP R-LO HRDI TELESCOPE BARREL TEMP 44821
HRPTSBARTMP Y-LO HRDI TELESCOPE BARREL TEMP 44825-35
HRPTSPBIMON Y-HI HRDI Telescope Barrel 44847
The following ALERT occurrences were detected:
MNEMONIC DESCRIPTION ORBITS
--------- ------------ ------
No Alerts to report this report period.
______________________________________________________________________
APPENDIX C
CLOCK & SOLAR ARRAY RATE CORRECTIONS
Week ending 26 November 1999
CLOCK DRIFT RATE ADJUSTMENTS
ORBIT TIME CLOCK RATE CHANGE
----- ---- -----------------
44802 326/12:20 (22 Nov 99) from 41.2 to 20.6 msec/day
44835 328/16:30 (24 Nov 99) from 20.6 to 41.2 msec/day
44858 330/06:00 (26 Nov 99) from 41.2 to 20.6 msec/day
________________________________________________________________________
APPENDIX D
UARS BATTERY PERFORMANCE DATA
Week ending 26 November 1999
19 Nov 1999 - GMT Day 323 Beta = 74.9 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 -67.2/-89.6 -2.42/-3.36 +0.0/+0.0 16.3 0.000 0.0
2 +22.4/+0.0 +3.23/+1.66 +16.8/-14.8 27.5 1.037 13.4
3 +22.4/-22.4 +2.29/+1.34 +16.0/-14.4 27.4 1.035 12.9
26 Nov 1999 - GMT Day 330 Beta = 50.3 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 -56.0/-78.4 -3.68/-4.94 +0.0/+0.0 16.2 0.000 0.0
2 +84.0/+0.0 +5.47/+4.19 +28.4/-16.0 25.3 1.030 19.5
3 +22.4/-22.4 +4.51/+2.92 +27.2/-15.2 25.1 1.027 19.1
V/T LEVEL CHANGES
ORB# TIME LVL FR-TO
----- --- ----------
no changes V/T 5
APPENDIX E
UARS ANOMALY REPORTS
Week ending 26 November 1999
NEW ANOMALY REPORTS GENERATED
AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
99-085 FOT 44810 327/0008 21603 512 kb playbacks errors
99-086 FOT 44823 327/2109 21606 TPF - No I channel
99-081 FOT 44843 329/0509 14170 Generic Late Acquisition
ANOMALY CLOSURE INFORMATION RECEIVED
AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
99-085 FOT 44810 327/0008 21603 512 kb playbacks errors
99-086 FOT 44823 327/2109 21606 TPF - No I channel
ANOMALY INVESTIGATION REPORTS GENERATED
AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
No new reports generated
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 Receiving 512 PB
99-081 FOT November 14170 Generic Late Acquisition
SEVNTFW99/48