UARS Weekly Status Report

9 September 2005




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                UARS WEEKLY STATUS REPORT - 09 SEP 2005

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

Nothing received.

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

Nothing received.

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

Nothing received.

***********
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.

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

Nothing received.
                  
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FOT
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                           REPORTING PERIOD

This  report covers 27 August 2005 (Orbit 76415, GMT Day 239)  through
02 September 2005 (Orbit 76519, GMT Day 245).

                         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         240/2003      76442     POWER ON
       HALOE         241/0406      76447     POWER OFF
       HALOE         241/2242      76458     POWER ON
       HALOE         242/0716      76464     POWER OFF
       HALOE         242/1118      76467     POWER ON
       HALOE         242/1414      76469     POWER OFF
       HALOE         243/0836      76480     POWER ON
       HALOE         243/1631      76485     POWER OFF
       SOLSTICE      243/1812      76486     POWER ON - DAY-ONLY
       SOLSTICE      243/1952      76487     DAY-ONLY TO FULLTIME


The beta angle ranged between the angles of 65.9 degrees to 59.9
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 3.80 to 3.15 degrees C.  Additional
battery performance data for each battery on 26 August 2005 and 02
September 2005 are provided in Appendix D.

The clock error ranged from 11.8 to -11.9 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       =    16
    SOLSTICE  =    02
    HALOE     =    03


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

    FOT       =    04

Five (5) Anomaly Reports remained OPEN at the end of this report
period (see Appendix E).


                        GROUND SYSTEM OPERATION

Four (4) 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

This week the FOT has been closely monitoring the condition of battery
2.  Battery 2 continues its slow drop in temperature.  Battery 3 has
been working surprisingly well under the increased load that it has
been put under.  During the 241/1819 contact, our latest tweak to TMON
45 and 46 was made.  TMON 45 was adjusted to take battery 2 off relay
once FCT + 1 count was reached.  This was done to keep the C/D ratio
on battery 2 in check as it was increasing with the increase in S/C
beta angle.  TMON 46 was also modified to keep battery 2 off relay
until 7 « minutes into S/C night.  This change was necessary due to
battery 3 actually charging battery 2 when it came back on relay.

The FOT has also taken the first steps to begin orbit-lowering
activities.  On the 242/1916 contact the FOT successfully executed the
FSW patch to allow for 4 thruster mode on the PM.  In order to verify
that the PM would behave as expected with the new patch on-board, the
FOT had planned a short calibration burn of 6 seconds using all 4-
translation thrusters.  This test was planned for and carried out with
out any problems on the 244/1330 support.  All 4 thrusters fired as
expected and the A/C attitude thrusters also fired in a timely manner.

In anticipation of longer burns, 2 more calibration burns of
increasingly longer lengths are tentatively scheduled for 14 September
2005 (DOY 257) and 22 September 2005 (DOY 265).  A schedule for when
the 6 required orbit-lowering burns has also been settled upon.  Burn
1 will be on 29 September 2005 (DOY 272); burn 2 will be on 04 October
2005 (DOY 277); burn 3 will be on 06 October 2005 (DOY 279); burn 4
will be on 12 October 2005 (DOY 285); burn 5 will be on 18 October
2005 (DOY 291); and lastly burn 6 will be on 20 October 2005 (DOY
293).  There will be no instruments operating during the month of
October due to the aggressive burn plan activities.  HALOE will resume
operations after the burns have completed and we have completed the
yaw back to forward flight.

Lastly, the UARS spacecraft flight software rejected the ephemeris
that was created for 02 September 2005, (DOY 245).  This was due to
the fact that the calibration burn that was done the day prior moved
UARS enough to require the FOT to open the ephemeris check window.
This small change was made and a new ephemeris was uploaded, accepted
and began propagating as expected.  In the future, the FOT will have
to remember to open the windows for any ephemeris loads sent after any
burns.


                               MEETINGS

The FOT attended the De-boost status meeting on 29 August 2005.
During this meeting FDF proposed burns of 18 minutes in length for
each orbit lowering burn instead of the 15-minute burns that they
initially had suggested might be needed.  These burns are based on a
duty cycle of ~ 90%.

The FOT also attended the weekly Technical Working Group meeting on 01
September 2005.  FDF predicts that UARS fuel remaining onboard is in
the range of 354 lbs plus or minus 3 lbs.  UARS telemetry shows there to be
353.5 lbs of fuel remaining.


                       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 roughly 15 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 02 September 2005

ORBIT   AOS        NO.      SUBSYS      REASON
-----   ---        ---      ------      ------
76433   240/0543   05-288   OBC/CLK     CLK ADJ FR 0.0 TO 20.6 MSEC/DAY
76439   240/1453   05-289   OBC/CLK     CLK ADJ FR 20.6 TO 41.2 MSEC/DAY
76442   240/2003   05-290   HALOE       POWER ON - PART ONE
76444   240/2246   05-291   HALOE       POWER ON - PART TWO
76447   241/0406   05-292   HALOE       POWER OFF
76454   241/1527   05-293   OBC/CLK     CLK ADJ FR 41.2 TO 20.6 MSEC/DAY
76455   241/1637   05-294   OBC         OBC TABLE DUMPS
76456   241/1711   05-295   OBC/CLK     CLK ADJ FR 20.6 TO 0.0 MSEC/DAY
76456   241/1819   05-296   TMON        TMON 45/46 CHANGE
76457   241/1856   05-297   OBC         OBC BANK DUMPS
76458   241/2242   05-290   HALOE       POWER ON - PART ONE
76460   242/0032   05-291   HALOE       POWER ON - PART TWO
76464   242/0716   05-292   HALOE       POWER OFF
76467   242/1118   05-290   HALOE       POWER ON - PART ONE
76468   242/1229   05-291   HALOE       POWER ON - PART TWO
76469   242/1414   05-292   HALOE       POWER OFF
76470   242/1554   05-298   OBC         MEMORY MONITOR
76472   242/1916   05-300   OBC/PM      PM PATCH (4-THRUSTER)
76472   242/1916   05-299   OBC/CLK     CLK ADJ FR 0.0 TO 20.6 MSEC/DAY
76473   242/2100   05-301   OBC         OBC BANK DUMPS
76473   242/2135   05-302   OBC/CLK     CLK ADJ FR 20.6 TO 41.2 MSEC/DAY
76480   243/0836   05-290   HALOE       POWER ON - PART 1
76481   243/1016   05-291   HALOE       POWER ON - PART 2
76485   243/1631   05-293   HALOE       POWER OFF
76486   243/1812   05-303   SOLSTICE    POWER ON - DAY ONLY
76487   243/1952   05-304   SOLSTICE    POWER ON - FULLTIME
76489   243/2239   05-305   OBC/CLK     CLK ADJ FR 41.2 TO 20.6 MSEC/DAY
76493   244/0430   05-306   OBC/CLK     CLK ADJ FR 20.6 TO 0.0 MSEC/DAY
76498   244/1330   05-307   PM          OA CAL BURN
76517   245/1909   05-308   OBC/CLK     CLK ADJ FR 0.0 TO 20.6 MSEC/DAY


                              APPENDIX B
                  OUT-OF-LIMITS & ALERTS OCCURRENCES
                     Week ending 02 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 02 September 2005

                     CLOCK DRIFT RATE ADJUSTMENTS

ORBIT          TIME                   CLOCK RATE CHANGE
-----          -----                  -----------------
76433          240/0546               CLK ADJ FR 0.0 TO 20.6 MSEC/DAY
76439          240/1505               CLK ADJ FR 20.6 TO 41.2 MSEC/DAY
76454          241/1530               CLK ADJ FR 41.2 TO 20.6 MSEC/DAY
76456          241/1720               CLK ADJ FR 20.6 TO 0.0 MSEC/DAY
76472          242/1924               CLK ADJ FR 0.0 TO 20.6 MSEC/DAY
76473          242/2137               CLK ADJ FR 20.6 TO 41.2 MSEC/DAY
76489          243/2239               CLK ADJ FR 41.2 TO 20.6 MSEC/DAY
76493          244/0430               CLK ADJ FR 20.6 TO 0.0 MSEC/DAY
76517          245/1909               CLK ADJ FR 0.0 TO 20.6 MSEC/DAY


                              APPENDIX D
                     UARS BATTERY PERFORMANCE DATA
                     Week ending 02 September 2005

     26 August 2005 - GMT Day 238 Beta = 62.1 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  -3.68/ -4.63  +00.0/+00.0  04.6     0.00      0.0
2   -700.0/-700.0  +7.74/ +3.87  +22.0/-17.6  25.8     1.09     11.8
3    196.0/-700.0  +3.87/ +2.60  +19.2/-20.8  25.6     1.03     16.3


     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


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



                              APPENDIX E
                         UARS ANOMALY REPORTS
                     Week ending 02 September 2005

                     NEW ANOMALY REPORTS GENERATED
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 CLOSURE INFORMATION RECEIVED
AR NO.    SUBSYS    ORBIT     TIME      CDS       PROBLEM/DATA LOSS
------    ------    -----     ----      ---       -----------------
-None this report period.

                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
05-043    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