UARS Weekly Status Report

16 September 2005




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                UARS WEEKLY STATUS REPORT - 16 SEP 2005

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

Nothing received.

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

Nothing received.

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

Nothing received.

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HALOE 
***********

Nothing received.

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

Nothing received.

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

Nothing received.

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

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  03 September 2005 (Orbit  76520,  GMT  Day  246)
through 09 September 2005 (Orbit 76625, GMT Day 252).

                         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
       SOLSTICE      246/0241      76522     POWER ON
       HALOE         246/1547      76530     POWER ON
       HALOE         247/2345      76550     POWER OFF
       HALOE         248/0335      76552     POWER ON


The beta angle ranged between the angles of 59.7 degrees to 34.0
degrees for this report period.  The beta angle is now decreasing
towards a minimum angle of 2 degrees on 17 September 2005 (DOY 260).

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 2.56 to 2.23 degrees C.  Additional
battery performance data for each battery on 02 September 2005 and 09
September 2005 are provided in Appendix D.

The clock error ranged from 08.4 to -10.4 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  =    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       =    05
    SOLSTICE  =    01
    HALOE     =    04


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

    FOT       =    01

Two (2) Anomaly Reports remained OPEN at the end of this report period
(see Appendix E).


                        GROUND SYSTEM OPERATION

One (1) operational support problem 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

This week the FOT continues to closely monitor the condition of
battery 2 and battery 3.  Battery 2 and 3 have not been sharing load
well since the cell failure on battery 2.  Battery 3 carries roughly
2/3 of the power load while battery 2 provides the remaining 1/3.  As
the beta angle goes lower, this discontinuity is slowly getting
exaggerated.  NASA power branch has been providing daily support in
monitoring the UARS battery condition.  The FOT has been authorized to
disable all platform and instrument heaters on the SSPP.  This will be
done at the earliest available opportunity.

Analysis of the 6-second calibration burn indicated that one of the
translation thrusters may not have opened fully for the duration of
the burn.  This reduced the overall effectiveness of the burn.  The
FOT was expecting near 95% duty cycle for this short burn.  The
calculated duty cycle for the 6-second calibration burn was
approximately 87%

The FOT has selected a pass during which to do a longer 2nd 4 thruster
calibration burn.  This burn will be done on 14 September 2005 (DOY
257) during the 1447 - 1514 support.  The burn will be 30 seconds in
length with a start time of 257/14:55:00Z.  The primary objective of
this burn is to see attitude and translation thrusters firing, off-
pulsing.  A secondary goal of the longer burn is get a better idea on
what the actual duty cycle is using 4-thruster mode.



                               MEETINGS

There was no De-boost status meeting this week due to the holiday on
Monday.  The next De-boost status meeting is scheduled for 12
September 2005.

The FOT attended the weekly Technical Working Group meeting on 08
September 2005.  The details for the 30-second calibration burn were
discussed with FDF.  The FOT also identified several products that FDF
would need to provide in the event of a no-burn or partial burn.


                       FUTURE SIGNIFICANT EVENTS

The next UARS Yaw slew is scheduled for 17 September 2005 (DOY 260).
This maneuver will be a Forward to Reverse Flight maneuver (Northern
Hemisphere viewing).

A second 4-thruster calibration burn of 30 seconds in length is
scheduled for 14 September 2005 (DOY 257).


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 09 September 2005

ORBIT   AOS        NO.      SUBSYS      REASON
-----   ---        ---      ------      ------
76521   246/0202   05-309   OBC         EPH TOLERANCE OPEN-NEW LOAD
76522   246/0241   05-310   SOLSTICE    POWER OFF
76522   246/0241   05-309   OBC         EPH TOLERANCE DEFAULT
76530   246/1547   05-311   HALOE       POWER ON - PART ONE
76530   246/1621   05-312   HALOE       POWER ON - PART TWO
76544   247/1503   05-313   OBC/CLK     CLK ADJ FR 20.6 TO 0.0 MSEC/DAY
76550   247/2345   05-314   HALOE       POWER OFF
76552   248/0335   05-315   HALOE       POWER ON
76590   250/1526   05-316   OBC         OBC/PMON
76622   252/1850   05-317   OBC         TABLE 58 DUMP


                              APPENDIX B
                  OUT-OF-LIMITS & ALERTS OCCURRENCES
                     Week ending 09 September 2005

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 09 September 2005

                     CLOCK DRIFT RATE ADJUSTMENTS

ORBIT          TIME                   CLOCK RATE CHANGE
-----          -----                  -----------------
76544          247/1503               CLK ADJ FR 20.6 TO 0.0 MSEC/DAY


                              APPENDIX D
                     UARS BATTERY PERFORMANCE DATA
                     Week ending 09 September 2005

     02 September 2005 - GMT Day 245 Beta = 59.9 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  -2.74/ -3.99  +00.0/+00.0  04.6     0.00      0.0
2   -700.0/-700.0  +1.34/ +0.40  +16.8/-13.2  25.4     1.08      7.2
3    128.8/-291.2  +5.14/ +3.55  +27.2/-24.0  25.1     1.02     21.2

     09 September 2005 - GMT Day 252 Beta = 34.0 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    728.0/ 728.0  -2.74/ -3.68  +00.0/+00.0  04.6     0.00      0.0
2   -700.0/-700.0  +3.87/ +2.91  +24.0/-17.6  24.5     1.05     11.5
3    179.2/-291.2  +6.43/ +5.14  +29.6/-23.2  24.5     1.01     24.3


     V/T LEVEL CHANGES
ORB#           AOS TIME   LVL FR-TO
-----          --------   ---------
-None this report period.



                              APPENDIX E
                         UARS ANOMALY REPORTS
                     Week ending 09 September 2005

                     NEW ANOMALY REPORTS GENERATED
AR NO.    SUBSYS    ORBIT     TIME      CDS     PROBLEM/DATA LOSS
------    ------    -----     ----      ---     -----------------
05-044    FOT       76540     247/0746  30832   Generic Late Acquisition

                 ANOMALY CLOSURE INFORMATION RECEIVED
AR NO.    SUBSYS    ORBIT     TIME      CDS     PROBLEM/DATA LOSS
------    ------    -----     ----      ---     -----------------
05-043    FOT       76458     241/2148  40662   Late Acquisition
05-032    FOT       76465     242/0757  30832   Generic Late Acquisition
05-045    FOT       76496     244/0901  40682   Late Acquisition/Equip @
WSGT
05-046    OBC       76518     245/2125  N/A     Flight Segment Ephem Reject

                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
------    ------    -----     ----      ---       -----------------
05-042    MPS       76339     233/2347  N/A       BATTERY 2 DIFFV -700mV
05-044    FOT       See List  Sept 05   30832     Generic Late Acquisition