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UARS WEEKLY STATUS REPORT - 27 APR 2001
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***********
SOLSTICE
***********
Nothing received.
***********
SUSIM
***********
SUSIM was switched off for 18-22 April because of spacecraft power
constraints. Otherwise SUSIM performed its daily solar scans this
past week during periods of predicted UARS telemetry.
***********
ACRIM
***********
Nothing received.
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PEM
***********
At the present time, PEM energy deposition from its spectrometers is not
being generated. Recent data configuration changes have affected PEM software
causing multiple failures. These failures are being reviewed by the PEM team.
In order to correct for new telemetry requirements, PEM will need to update
processing code with a patch delivery. The delivery patch may include changes
which would allow the PEM software to execute on a DEC Alpha machine. GSFC is
helping PEM with some DEC Alpha particulars which have caused PEM level 3
code to fail on DEC Alpha machines (software below level 3 executes on the
DEC Alpha).
PEM has examined its processed files of the rehost machine and has found
that no differences exist in the Level 1 and Level 2 output files which were
generated the rehost when the same input data was used on CDHF and CDHFB.
PEM is now confident that output generated by PEM 3.32, Jobs 1 & 2, on the
rehost system is valid and correct.
The PEM team is working on replacing the PEM:: machine with a DEC Alpha
machine to be called PEM2K::. Tests of the NRT data transfer from CDHF2::
through PEM2K:: to the unix computer running the PEM GSE software show no
difference between equivalent NRT files transferred from PEM::. Thus, NRT
data from CDHF2:: is captured correctly on PEM2K::. Tests of the NRT data
transfer from CDHFB:: were not successful from both PEM:: and PEM2K::.
Results of the test of NRT data transfers from the rehost computer were
successful for individual files which exist on CDHFB::. PEM will participate
in the NRT data flow to capture NRT data from CDHFB:: when specified by GSFC.
PEM has been working with GSFC on allowing commanding of the PEM
instrument by creating DAPs on the PEM2K machine and submitting them to the
CMS. So far, this has not been achieved. It was discovered that PEM2K is
running Openwindows version 7.2-1 which operates differently across the
network than Openwindows version 7.1-2 (the CDHFB operating system). Compaq
is investigating to determine a solution. In the mean time, Steve Bove made
some suggestions which seem to have improved the PEM2K:: to UCMS:: image
execution ability; however, the CMS has had troubles recently and it appears
that the UCMS:: definitions for PEM2K:: must not be correct on the UCMS:: node.
PEM is waiting on a reply back from GSFC.
Updated HEPS calibration parameters have been finalized and are ready for
delivery. Updated MEPS quality calibration files have been finalized and are
ready for delivery. Level 3 software errors, discovered by Dr. Dean Pesnell,
have been fixed; his suggestions have been incorporated with in the PEM
production code. Both updated HEPS and MEPS calibration data, along with the
Level 3 code changes, will influence the in-situ energy deposition predictions,
so new versions of PEM energy deposition Level 3 files will be generated.
*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.
***********
HALOE
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Nothing received.
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MLS
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Nothing received.
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HRDI
***********
Nothing received.
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WINDII
***********
Nothing received.
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MPG
***********
Daily processing of instrument Daily Activity Plans continues
with no problems. Instrument operations schedule is now complete
to 30 May 2001.
***********
CDHF
***********
HIGHLIGHTS
----------
- All level 0 data from the power outage time frame are available.
UARS CDHF REHOST
----------------
- Additional 2 weeks have been requested to confirm "puts" to silo. Once this is
done we are able to go operational.
We are anxious to go operational on the REHOST due to resource requirements
needed to run two clusters.
***********
FOT
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REPORTING PERIOD
This report covers 14 April 2001 (Orbit 52321, GMT Day 104) through 20 April
2001 (Orbit 52425, GMT Day 110).
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 106/0241 52457 Power OFF
SUSIM 109/0006 52500 Power OFF
ACRIM 109/0006 52500 Power OFF
PEM 109/0106 52501 Power OFF
HRDI 109/2313 52515 Low Power
A Reverse-to-Forward Yaw Around maneuver (number 98) was successfully
executed in Orbit 52510 beginning 109/16:01:03 and completing at 109/16:38:00
on 19 April 2001. The SOLSTICE instrument was in day only and all other
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 55.9 minutes. Post maneuver
analysis of data indicate that during the Yaw Around, the end-of-night load
bus voltage was 23.90 volts and the average depths of discharge (DODs) on
Batteries 2 and 3 were approximately 22.8 and 23.0 percent respectively. The
next (forward-to-reverse) YAW is scheduled for 30 May 2001 (DOY 150).
The beta angle ranged between the angles of -24.2 degrees to +1.4 degrees for
this report period. The beta angle is now increasing towards a maximum angle
of 74 degrees on 09 May 2001 (DOY 129).
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 1.3 and 1.6 degrees C. Additional battery performance data for
each battery on 13 April 2001 and 20 April 2001 are provided in Appendix D.
The clock error ranged from Ð13.2 to 13.4 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.
¥ OUT-OF-LIMITS = 02
ALERTS = 00
The following real-time command sheets were executed for the listed
operational element(s) during this report period (see Appendix A).
¥ FOT = 18
¥ HALOE = 01
¥ SUSIM = 01
¥ ACRIM = 01
¥ PEM = 01
¥ HRDI = 01
UARS Anomaly Reports initiated during this report period are listed in
Appendix E and summarized below.
¥ FOT = 02
One (1) Anomaly Report remained OPEN at the end of this report period (see
Appendix E).
TRANSPONDER FREQUENCIES:
· Transponder A: 00/316 - 2287.496493
· Transponder B: 01/087 - 2287.499152
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 01/067 show the observatory data loss to be 300
hours, 3 minutes, 5.464 seconds. This shows an increase of 1 minute and
52.704 seconds since the last report period. This is a 0.39 percent data
loss, which equals a 99.61 percent data capture for the mission.
· 15.424 seconds on Day 107 due to a Data Hit,
· 1 minute and 37.280 seconds on Day 108 due to a Data Hit.
OTHER SIGNIFICANT EVENTS
UARS SATELLITE OPERATIONS
UARS is using both the Fine Sun Sensor (FSS) and the Three Axis Magnetometer
(TAM) as inputs to UFLTR this week. The FOT is pleased with their
performance, but continues to make adjustments to the TAM alignment to
improve its performance and UARSÕ attitude.
The FSW patch that will improve the magnetic field model from a 5th order to
7th order solution has been completed. The patch requires one further test
next week before the planned uplink date of 25 April 2001.
MEETINGS
The FOT attended a UARS TAC RS Replacement Meeting on Wednesday, April 18,
2001.The FOT attended the UARS SERB Meeting on Wednesday, April 18, 2001.
FUTURE SIGNIFICANT EVENTS
The next UARS Yaw slew is scheduled for 30 May 2001 (DOY 150). 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 20 April 2001
ORBIT AOS NO. SUBSYS REASON
----- --- --- ------ ------
52430 104/0750 01-231 NBTR NOOPS D-104
52437 104/1805 01-232 NBTR NOOPS D-105
52443 105/0420 01-233 OBC/CLK Clk Adj 0.00 to -20.6 msec/day
52444 105/0646 01-232 NBTR NOOPS D-105
52452 105/1805 01-234 NBTR NOOPS D-106
52457 106/0241 01-235 HALOE Power OFF
52459 106/0605 01-236 OBC/CLK Clk Adj -20.6 to 0.00 msec/day
52460 106/0754 01-234 NBTR NOOPS D-106
52465 106/1443 01-237 OBC/CLK Clk Adj 0.00 to 20.6 msec/day
52478 107/1207 01-238 OBC/CLK Clk Adj 20.6 to 0.00 msec/day
52483 107/2010 01-239 OBC/TAM MAGMOD Time Update
52488 108/0424 01-240 OBC Clk Adj fr 0.00 to -20.6 msec/day
52493 108/1211 01-241 NBTR PBK
52500 109/0006 01-242 SUSIM Power OFF
52500 109/0006 01-243 ACRIM Power OFF
52501 109/0106 01-244 PEM Power OFF
52501 109/0106 01-245 SOLSTICE TO DAY OPS ONLY
52508 109/1209 01-246 OBC/CLK Clk Adj -20.6 to 0.00 msec/day
52510 109/1529 01-250 OBC/ACS YAW MANEUVER
52510 109/1529 01-249 OBC/CLK Clk Adj 0.00 to 20.6 msec/day
52510 109/1529 01-247 OBC/TAM TAM TO MONITOR MODE
52512 109/1842 01-248 OBC/TAM TAM TO UPDATE MODE
52515 109/2313 01-251 HRDI Low Power
52525 110/1617 01-252 OBC Clk Adj fr 20.6 to 0.00 msec/day
________________________________________________________________________
APPENDIX B
OUT-OF-LIMITS & ALERTS OCCURRENCES
Week ending 20 April 2001
The following Out-Of-Limits occurrences were detected:
MNEMONIC STATE DESCRIPTION ORBITS
-------- ----- ----------- ------
HRIFESURVTMP Y-HI HRDI IFE Survival Htr Temp 52517
HRRADTEMP Y-HI HRDI Radiator Temp 52517
The following ALERT occurrences were detected:
MNEMONIC DESCRIPTION ORBITS
-------- ----------- ------
-None this report period
_____________________________________________________________________________
APPENDIX C
CLOCK & SOLAR ARRAY RATE CORRECTIONS
Week ending 20 April 2001
CLOCK DRIFT RATE ADJUSTMENTS
ORBIT TIME CLOCK RATE CHANGE
----- ----- -----------------
52443 105/0420 Clk Adj fr 0.00 to -20.6 msec/day
52459 106/0605 Clk Adj fr -20.6 to 0.00 msec/day
52465 106/1443 Clk Adj fr 0.00 to 20.6 msec/day
52478 107/1207 Clk Adj fr 20.6 to 0.00 msec/day
52488 108/0424 Clk Adj fr 0.00 to -20.6 msec/day
52508 109/1209 Clk Adj fr -20.6 to 0.00 msec/day
52510 109/1529 Clk Adj fr 0.00 to 20.6 msec/day
52525 110/1617 Clk Adj fr 20.6 to 0.00 msec/day
________________________________________________________________________
APPENDIX D
UARS BATTERY PERFORMANCE DATA
Week ending 20 April 2001
13 Apr 2001 - GMT Day 103 Beta = 27.8 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/+44.8 -3.05/-4.31 +0.0/+0.0 13.0 0.000 0.0
2 +11.2/-100.8 +6.44/+5.15 +29.6/-15.6 24.0 1.040 21.8
3 +22.4/-67.2 +5.47/+3.87 +28.8/-16.0 23.8 1.030 21.7
20 Apr 2001 - GMT Day 110 Beta = 01.4 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 +621.6/+280.0 -3.68/-4.94 +0.0/+0.0 12.3 0.000 0.0
2 +22.4/-67.2 +5.15/+3.87 +28.8/-12.8 25.1 1.020 20.5
3 +22.4/-67.2 +3.87/+2.60 +28.0/-12.8 25.0 1.020 20.0
V/T LEVEL CHANGES
ORB# TIME LVL FR-TO
---- ---- ---------
-no changes V/T 5
_____________________________________________________________________________
APPENDIX E
UARS ANOMALY REPORTS
Week ending 20 April 2001
NEW ANOMALY REPORTS GENERATED
AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
01-019 FOT 52501 109/0146 14170 Generic Late Acquisition
01-019 FOT 52506 109/0944 14170 Generic Late Acquisition
ANOMALY CLOSURE INFORMATION RECEIVED
AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
-None this report period
ANOMALY INVESTIGATION REPORTS GENERATED
AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
-None this report period
OPEN ANOMALY REPORTS
AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
01-019 FOT see list Apr 01 14170 Generic Late Acquisition
SEVNTFW01/16