UARS Weekly Status Report

07 September 2001




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                UARS WEEKLY STATUS REPORT - 07 SEP 2001

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***********
SOLSTICE
***********

Nothing received.

***********
SUSIM
***********

SUSIM has completed its daily solar scans this past week during
periods of predicted UARS telemetry.

As requested, we are verifying NRT files built on the PACOR-A system
versus the CDHF versions.

We are building our final calibrations to be used for reprocessing
the latest level 1 data to level 3 at NRL.

***********
ACRIM
***********

Nothing received.

***********
PEM
***********

***** ALL PEM COMMUNICATION SHOULD NOW BE THROUGH THE PEM2K:: NODE *****

     PEM is saddened by the shutdown of UARS and appreciates all of the 
efforts of GSFC in the past and present of UARS.

     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).  Currently, PEM has requested GSFC assistance with compiling for
the DEC Alpha since the GSFC executables run on the Alpha and SwRI's compiled
versions do not.

    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.

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HALOE 
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Nothing received.

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MLS
***********

Nothing received.

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HRDI
***********

Nothing received.

***********
WINDII
***********

Nothing received.

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MPG
***********

The MPG participated in the UARS Monthly Status Review
Meeting on 05 September 2001. 

On 06 September 2001 the MPG participated in the weekly UARS
Technical Team Meeting.  This series of meetings is being
held to discuss contingencies since it appears that FY 2002
funds will be insufficient to continue collection of
science data by the UARS instruments.

Processing of instrument Daily Activity Plans continues
with no problems.

***********
CDHF
***********

Nothing received.
                  
***********
FOT
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                          REPORTING PERIOD

This report covers 25 August 2001 (Orbit 54421, GMT Day 237) through 31 August 
2001 (Orbit 54525, GMT Day 243).

                        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
         MLS          237/2224     54435     Power OFF
         HALOE        238/0012     54436     Power ON

The beta angle ranged between the angles of 46.3 degrees to 39.6 degrees for 
this report period.  The beta angle is now decreasing towards a minimum angle 
of 0 degrees on 11 September 2001 (DOY 254).

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 1.2 to 1.3 degrees C.  Additional battery performance data for each 
battery on 24 August 2001 and 31 August 2001 are provided in Appendix D.

The clock error ranged from Ð12.1 to 10.0 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            =  20
¥     HALOE          =  01
¥     MLS            =  01



UARS Anomaly Reports initiated during this report period are listed in Appendix 
E and summarized below.

¥     FOT            =  02


Zero (0) Anomaly Report remained OPEN at the end of this report period (see 
Appendix E).

TRANSPONDER FREQUENCIES:
· Transponder A:  00/316  - 2287.496493
· Transponder B:  01/119  - 2287.499116

                        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 01/242 show the observatory data loss to be 303 hours, 09 
minutes, 13.504 seconds. This shows a loss of 15.808 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.

The increase of 15.808 seconds of data loss occurred over three (3) days:
· 27.840 seconds on Day 236 due to a Data Hit
· 22.208 seconds on Day 237 due to a Data Hit
· 09.760 seconds on Day 238 due to a Data Hit


                       OTHER SIGNIFICANT EVENTS

                       UARS SATELLITE OPERATIONS

The FOT continues to support and plan for the possible decommissioning of the 
UARS spacecraft.  A 3-minute calibration burn has been scheduled for 06 
September 2001.  The time of the burn has been set for 1310 GMT during the 
1302-1327 GMT event.  This burn should give the FOT and FDF a good handle on 
the duty cycle and efficiency of the thrusters.  All issues with FDF product 
deliveries have been worked out and next TuesdayÕs products should include pre 
and predicted post burn data.

                             MEETINGS

The UARS FOT attended a UARS Readiness Meeting on Monday, August 27, 2001.
The UARS FOT attended a UARS FDF Meeting on Monday, August 27, 2001.
The UARS FOT attended a UARS Technical Team Meeting on Thursday, August 30, 
2001.

                      FUTURE SIGNIFICANT EVENTS

The next UARS Yaw slew is scheduled for 11 September 2001 (DOY 254).  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 31 August 2001

ORBIT     AOS          NO.       SUBSYS     REASON
-----     ---          ---       ------     ------
54435     237/2224     01-532    MLS        Power OFF
54436     238/0012     01-533    HALOE      Power ON
54438     238/0414     01-534    OBC        Clk Adj fr 20.6 to 0.00 msec/day
54440     238/0654     01-535    NBTR       D 238 NOOPS
54446     238/1716     01-535    NBTR       D238 NOOPS
54447     238/1759     01-536    NBTR       D239 NOOPS
54454     239/0557     01-536    NBTR       D 239 NOOPS
54461     239/1716     01-536    NBTR       D239 NOOPS
54462     239/1801     01-537    NBTR       D240 NOOPS
54470     240/0656     01-537    NBTR       D 240 NOOPS
54476     240/1620     01-538    OBC        RELOAD RTS 1
54476     240/1717     01-537    NBTR       D240 NOOPS
54478     240/1900     01-539    OBC        Clk Adj fr 0.00 to 20.6 msec/day
54484     241/0559     01-540    NBTR       Day 241 NOOPS
54492     241/1802     01-540    NBTR       Day 241 NOOPS
54492     241/1802     01-541    NBTR       Day 242 NOOPS
54498     242/0418     01-542    OBC        Clk Adj fr 20.6 to 0.00 msec/day
54499     242/0600     01-541    NBTR       Day 242 NOOPS
54506     242/1718     01-541    NBTR       Day 242 NOOPS
54507     242/1802     01-543    NBTR       Day 243 NOOPS
54515     243/0742     01-543    NBTR       NOOPS D-243
54522     243/1802     01-544    NBTR       NOOPS D-244

___________________________________________________________________________

                             APPENDIX B
               OUT-OF-LIMITS & ALERTS OCCURRENCES
                   Week ending 31 August 2001

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 31 August 2001

                    CLOCK DRIFT RATE ADJUSTMENTS

ORBIT     TIME         CLOCK RATE CHANGE
-----     -----        -----------------
54438     238/0416     Clk Adj fr 20.6 to 0.00 msec/day
54478     240/1902     Clk Adj fr 0.00 to 20.6 msec/day
54498     242/0419     Clk Adj fr 20.6 to 0.00 msec/day
_______________________________________________________________________________

                             APPENDIX D
                    UARS BATTERY PERFORMANCE DATA
                      Week ending 31 August 2001


     24 August 2001 - GMT Day 236 Beta = 45.9 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    +728.0/+728.0   -3.05/-3.99   +0.0/+0.0      12.0      0.000      0.0
2    +11.2/-123.2    +5.15/+4.19   +26.0/-14.4    25.4      1.030      19.7
3    +22.4/-50.4     +4.51/+3.23   +25.6/-14.4    25.4      1.020      19.6


     31 August 2001 - GMT Day 243 Beta = 39.6 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    +728.0/+728.0   -2.73/-3.99   +0.0/+0.0      12.0      0.000      0.0
2    +11.2/-89.6     +6.11/+4.83   +27.2/-15.2    24.2      1.030      21.4
3    +22.4/-56.0     +5.15/+3.87   +27.2/-15.2    24.0      1.020      21.1


     V/T LEVEL CHANGES
ORB#           TIME     LVL FR-TO
-----          ----     ---------
-no changes     V/T 5

_______________________________________________________________________________

                               APPENDIX E
                       UARS ANOMALY REPORTS
                     Week ending 24 August 2001

                  NEW ANOMALY REPORTS GENERATED
AR NO.     SUBSYS     ORBIT     TIME       TTR     PROBLEM/DATA LOSS
------     ------     -----     ----       ---     -----------------
01-052     FOT        54424     237/0555   14171   Generic Drop Out
01-053     FOT        54494     241/2100   24026   Late Acq (4:33)


                 ANOMALY CLOSURE INFORMATION RECEIVED
AR NO.     SUBSYS     ORBIT     TIME       TTR     PROBLEM/DATA LOSS
------     ------     -----     ----       ---     -----------------
01-045     FOT        see list  August 01  14170   Generic Late Acquisition
01-052     FOT        54424     237/0555   14171   Generic Drop Out
01-053     FOT        54494     241/2100   24026   Late Acq (4:33)


                  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
------     ------     -----     ----       ---     -----------------
-None this report period

           SEVNTFW01/33