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UARS WEEKLY STATUS REPORT - 23 May 2003
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SOLSTICE
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Nothing received.
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SUSIM
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SUSIM resumed operations on May 19 after the
shutdown for the yaw-around. Since then, the instrument has
successfully gathered all of its daily mid resolution, weekly
offset, and O2 occultation scans this past week during periods of
UARS telemetry or tape recording segments.
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ACRIM
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Nothing received.
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PEM
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The PEM web site has moved. It has a new URL. Access the PEM web site
using http://wwwpem.space.swri.edu. The PEM data from the GUVI conjunction
periods has moved to http://wwwpem.space.swri.edu/guvi-pem.html.
Level 2 PEM HEPSA data files are being reprocessed for submission to the
DAAC. This data has been designated as version 2; however, there is no format
difference from the version 1 data format. Version 2 HEPSA data is being
generated because it was discovered that there exists processing errors within
some of the HEPSA version 1 data files. Thus, if you are using any HEPSA
version 1 data files from the DAAC, please replace them with the version 2
data files. Currently, HEPSA data between 1991274 and 2001365 has been
reprocessed and archived at the GSFC DAAC. SwRI is working on reprocessing
data PEM for 2002.
PEM continues to work with the GUVI team on the diagnosis of data from
the first conjunction period. Analysis of the two conjunction passes showed
that the aurora as detected by GUVI was at higher latitude than UARS.
GUVI images from other times from the first conjunction period show spatial
regions that both GUVI and PEM sampled when aurora was present. Separation
is several minutes to 10's of minutes when both instruments saw aurora.
PEM has seen no aurora during the second conjunction period. Due to a
spacecraft anomaly, no PEM data was collected during the third conjunction
period.
PEM continues to receive NMC data files from NOAA. No problems have
been encountered. NOAA has changed the binary structure of the NMC data and
PEM is now receiving two data streams, one in the original VAX format and the
other from their new binary format.
*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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HALOE resumed normal operations on May 21 after the yaw maneuver.
A replacement for the failed AIX IBM computer has been installed at
Langley and access to the HALOE plots and data files has been restored
via the HALOE Website.
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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
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Nothing received.
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FOT
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REPORTING PERIOD
This report covers 10 May 2003 (Orbit 63781, GMT Day 130) through
16 May 2003 (Orbit 63886, GMT Day 136).
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 133/0438 63825 POWER OFF
PEM 133/2006 63839 POWER OFF
SUSIM 134/2150 63855 POWER OFF
A Forward-to-Reverse Yaw Around maneuver (number 119) was successfully
executed in Orbit 63881 beginning 136/15:43:10Z and completing at
136/16:20:20Z on 16 May 2003. All instruments were in their off or
standby mode (except for SOLSTICE in day-only). Due to the SA
position at 269 degrees, the effective night length of the spacecraft
after the maneuver was approximately 57.89 minutes. Post maneuver
analysis of data indicate that during the Yaw Around, the end-of-night
load bus voltage was 25.12 volts and the average depths of discharge
(DODs) on Batteries 2 and 3 were approximately 20.97 and 20.39 percent
respectively. The next (reverse-to-forward) YAW is scheduled for 14
June 2003 (DOY 165).
The beta angle ranged between the angles of 21.6 degrees to 1.5
degrees for this report period. The beta angle is now increasing
towards a maximum angle of 35 degrees on 31 May 2003 (DOY 151).
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 0.64 to 1.27 degrees C. Additional
battery performance data for each battery on 09 May and 16 May 2003
are provided in Appendix D.
The clock error ranged from -10.2 to 11.2 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 = 04
HALOE = 01
PEM = 01
SUSIM = 01
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).
GROUND SYSTEM OPERATION
Three (3) 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
Two issues were found with the Eclipse ground system this week. The
first problem was very similar to the network anomaly of 12 April
2003. In April the root cause of the anomaly was the faulty CISCO
switch #1, which has since been replaced and loaded with new firmware.
The other switch, CISCO switch #2, was left alone following that
anomaly. In this week's anomaly CISCO switch #2 triggered a spanning
tree problem, which overloaded the operational network, but the new
switch #1 remained intact. Due to this fact, the problem was believed
to be due the old firmware. A MOCR was written and approved by the
NASA Mission Director and the new firmware was installed on switch #2
that afternoon. No signs of the anomaly were exhibited since this
install.
The second issue found was an issue with the derived LRVs in Eclipse.
The procedure to dump the tape recorder began triggering error
messages on 06 May 2003. Investigation of these messages lead to an
analysis of two derived LRVs that this procedure uses to verify proper
modes. These two derived LRVs were not updated correctly and after
several different tests, the FOT believes this to be due to the fact
that they do not come out of their initial state properly. The
Raytheon team has been notified and a DR was written. Until the
problem is resolved the online crew is manually verifying the proper
modes before continuing with the tape recorder dump procedure.
The FOT successfully completed another UARS yaw maneuver on 16 May
2003. The batteries were set to VT-6 one orbit prior to the yaw and
will remain in VT-6 until telemetry indicates it should be set back to
the nominal VT-5 level. The VT-6 period will not exceed 3 days and
should be set back to VT-5 prior to any instrument turn-ons.
MEETINGS
The FOT also attended the weekly UARS DRB on 13 May 2003, to review
the open DRs and discuss the details of the next Eclipse software
delivery.
FUTURE SIGNIFICANT EVENTS
The next UARS Yaw slew is scheduled for 14 June 2003 (DOY 165). 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 16 May 2003
ORBIT AOS NO. SUBSYS REASON
----- --- --- ------ ------
63796 130/2342 03-109 OBC/CLK CLK ADJ FR 0.0 TO -20.6 MSEC/DAY
63815 132/0549 03-110 OBC/CLK CLK ADJ FR -20.6 TO 0.0 MSEC/DAY
63825 132/2256 03-111 HALOE POWER OFF
63839 133/2006 03-112 PEM POWER OFF
63855 134/2150 03-113 SUSIM POWER OFF
63880 136/1409 03-115 MPS V/T L-5 TO V/T L-6 (YAW)
63880 136/1448 03-115 MACS TAM TO MONITOR MODE
63881 136/1616 03-115 MACS SAFEHOLD RECONFIG/TAM ALGN MATRIX
63882 136/1645 03-115 MACS TAM TO UPDATE MODE/OPS MEM MON
63883 136/1832 03-116 OBC/CLK CLK ADJ FR 0.0 TO -20.6 MSEC/DAY
APPENDIX B
OUT-OF-LIMITS & ALERTS OCCURRENCES
Week ending 16 May 2003
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 16 May 2003
CLOCK DRIFT RATE ADJUSTMENTS
ORBIT TIME CLOCK RATE CHANGE
----- ----- -----------------
63796 130/2342 CLK ADJ FR 0.0 TO -20.6 MSEC/DAY
63815 132/0549 CLK ADJ FR -20.6 TO 0.0 MSEC/DAY
63883 136/1835 CLK ADJ FR 0.0 TO -20.6 MSEC/DAY
APPENDIX D
UARS BATTERY PERFORMANCE DATA
Week ending 16 May 2003
09 May 2003 - GMT Day 129 Beta = 28.0 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 -700.0/-700.0 -3.05/-4.62 +00.0/+00.0 07.7 0.000 0.0
2 +11.2/-78.4 +5.15/+3.87 +28.4/-15.2 23.8 1.040 20.2
3 +22.4/-72.8 +3.87/+2.60 +27.2/-15.2 23.8 1.030 19.9
16 May 2003 - GMT Day 136 Beta = 01.5 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 -700.0/-700.0 -3.68/-4.94 +00.0/+00.0 07.2 0.000 0.0
2 +11.2/-100.8 +4.51/+3.87 +28.0/-13.2 26.2 1.020 21.0
3 +22.4/-44.8 +3.87/+2.60 +26.8/-12.8 26.2 1.010 20.0
V/T LEVEL CHANGES
ORB# AOS TIME LVL FR-TO
----- -------- ---------
63880 136/1409 LV5 -> LV6
APPENDIX E
UARS ANOMALY REPORTS
Week ending 16 May 2003
NEW ANOMALY REPORTS GENERATED
AR NO. SUBSYS ORBIT TIME CDS PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
03-018 FOT 63829 133/0438 30832 Generic Late Acquisition
03-024 FOT 63852 134/1745 N/A Bad CISCO Switch No.2
03-025 FOT 63884 136/2016 32813 Data Dropout
ANOMALY CLOSURE INFORMATION RECEIVED
AR NO. SUBSYS ORBIT TIME CDS PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
03-019 FOT 63727 126/1008 N/A SEC Eclipse (PBK Problem)
03-020 FOT 63732 126/1334 32470 DROPOUTS ON I CHANNEL
03-021 FOT 63733 126/1943 32743 Late Acq 15 min recoverable
03-022 FOT 63742 127/0929 N/A PBK PROBLEM(REF 03-019)
03-023 FOT 63773 129/1105 32761 MULTIPLE DATA DROPOUTS
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
------ ------ ----- ---- --- -----------------
03-018 FOT See List May 03 30832 Generic Late Acquisition
03-024 FOT 63852 134/1745 N/A Bad CISCO Switch No.2
03-025 FOT 63884 136/2016 32813 Data Dropout