UARS Weekly Status Report

2 January 1998





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                UARS WEEKLY STATUS REPORT - 02 JANUARY 1998

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

Nothing received.

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

SUSIM successfully gathered its normal solar, offset, and occultation
scan data during this past week without apparent problems.

The half yearly calibration of the responsivity of the SUSIM working
channel have begun.

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

Nothing received.

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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
***********

Routine processing of instrument Daily Activity Plans continues
with no problems.  The MPG continues to assist the Project
Scientist with the scheduling of instrument operations.

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

The CDHF has received a total of 355 CD-ROM requests as of
2-January-98. There were no new orders received or shipped this week.
                        
The CDHF processed current day data through level 3 for all active
instruments. Additionally, CDHF personnel reprocessed: (R)= Requested
   (C) = Complete, (F)= Failed  (L) = Days remaining to reprocess.           
                 15 days PEM (3.32) Prod (1350R-725C=625L)
                  1 day CLAES (7.0) Eng (17R-1F=17L)
            
The CDHF will be implementing new login banners and issuing Rules of 
Behavior for users. This activity is based on updated NASA and Goddard
security requirements.

Pending software upgrades: IDL 5.0, OpenIngres. 
                  
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FOT
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REPORTING PERIOD

This report covers 19 December 1997 (Orbit 34283, GMT Day 354) through 26 
December 1997 (Orbit 34386, GMT Day 360).


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
     MLS       356/0535     34316       On
    WINDII     357/0642     34331       On
    WINDII     357/1002     34334       Off
    WINDII     357/1600     34337       On
     PEM       358/0026     34342     AXIS on

The beta angle reached a minimum angle of 0.0 degrees on 17 December 1997 (DOY 
351).  The beta angle is now increasing toward a maximum angle of 34.0 degrees 
on 01 January 1998 (DOY 001).

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 24.6 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 degrees C.  Additional battery performance data for each battery on 
20 December 1997 and 26 December 1997 are provided in Appendix D.

The clock error ranged from -11.4 to +10.6 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.

%     ALERTS            =     00
%     OUT-OF-LIMITS     =     02

The following real-time command sheets were executed for the listed operational 
element(s) during this report period (see Appendix A). 

%     FOT     03
%     HRDI    01
%     MLS     01
%     PEM     01
%     WINDII  03

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

%     FOT     02

TRANSPONDER FREQUENCIES:
     Transponder A:  97/343 - 2287.497007
     Transponder B:  97/344 - 2287.499121


GROUND SYSTEM OPERATION

Two (2) operational support problem(s) 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 97/352 show the observatory data loss to be 20 hours, 41 
minutes, 12.916 seconds (no change).  This is a 0.0378 percent data loss which 
equals a 99.9622 percent data capture for the mission.

The FOT is still working out the details of participating in the IP return-link 
telemetry test that the network is conducting.

No testing of the new CMS software release (R7B1V2) occurred this week.

UARS Test and Training Simulator (UTTS) testing of Q-channel data flow was 
conducted on 22 and 23 December 1997.  No successful OBC dumps were collected.  
Several hardware changes were made by ATSC along the connection between the 
UTTS VAX and the NASCOM lines.  It is not certain what the cause of the Q-line 
data flow problem is.  Further testing is scheduled.

All On-Board Computer Software Tools Facility (OBCSTF) terminals and printer 
were successfully connected and functioned properly on 23 December 1997.  One 
of two terminals and the laser printer had been experiencing communications 
line problems with the VAX computer located in Building-14 after the move back 
to the consolidated mission operations center.

Operational processing of level-0 telemetry analysis files on the UMPGAL 
computer (new MPG Alpha machine) continues in parallel with the CDHF computer 
system.  Level-0 file transfers between CDHF and UMPGAL failed completely on 22 
December 1997, preventing completion of level-0 processing on UMPGAL for that 
day.  File transfer problems continue to occur with a frequency of about two 
failures per week.  Unless this problem is rectified, level-0 processing on 
UMPGAL will not prove to be practical.  Parallel processing will continue 
indefinitely, but the CDHF system will be the primary source for FOT telemetry 
analysis products until the cause of the file transfer problem is isolated and 
corrected.  Until then, operational use of UMPGAL for processing will be 
considered unreliable.


OTHER SIGNIFICANT EVENTS

Monitoring of the magnetic field model performance continues.

FOT continues to improve a Power Profile for UARS based on the current status
of the Modular Power System.

FOT continues to support the new UARS ground system re-engineering effort.


MEETINGS

No UARS Battery telecon was held this week.  The next telecon has not been 
scheduled.


FUTURE SIGNIFICANT EVENTS

The next UARS Yaw Around Maneuver is currently scheduled for 16 January 1998 at 
016/13:25:14 UTC.

The UARS orbit altitude is dropping slowly and a drag makeup orbit adjust will 
probably be required in mid-1998.


FACILITIES

no change


PERSONNEL CHANGES

no change


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 26 December 1997

ORBIT        AOS      NO.     SUBSYS                 REASON
-----        ---      ---     ------                 -------  
34284     354/0258   97-631     OBC     Clk Adj fr 0.00 to 20.6 msec/day
34303     355/0910   97-632     OBC     Clk Adj fr 20.6 to 0.00 msec/day
34316     356/0535   97-633     MLS     Power ON
34331     357/0642   97-634   WINDII    Power ON
34334     357/1002   97-635   WINDII    Power OFF
34337     357/1600   97-636     HRDI    Heater Delay to 100 Amp-min
34337     357/1600   97-637   WINDII    Power ON
34342     358/0026   97-638     PEM     Power ON AXIS
34368     359/1724   97-639  OBC/CLOCK  Clk Adj fr 0.00 to 20.6 msec/day


_______________________________________________________________

APPENDIX B
                       OUT-OF-LIMITS & ALERTS OCCURRENCES
                          Week ending 26 December 1997

MNEMONIC     STATE         DESCRIPTION                     ORBITS
---------    -----        ------------                     ------
WIEUTEMP     Y-LO    WINDII EU Temperature               34283-327
HRPSEQBIMON  Y-HI    HRDI Quiet Bus Current Monitor      34325,64,68


The following ALERT occurrences were detected:

MNEMONIC                  DESCRIPTION                      ORBITS
---------                 ------------                     ------
 (none)



                                APPENDIX C
                   CLOCK & SOLAR ARRAY RATE CORRECTIONS
                       Week ending 26 December 1997

                      CLOCK DRIFT RATE ADJUSTMENTS

     ORBIT              TIME                 CLOCK RATE CHANGE
     -----              ----                 -----------------
     34284     354/02:58 (20 Dec 97)     from 00.0 to 20.6 msec/day
     34303     355/09:10 (21 Dec 97)     from 20.6 to 00.0 msec/day
     34368     359/17:24 (25 Dec 97)     from 00.0 to 20.6 msec/day


_______________________________________________________________

                              APPENDIX D
                    UARS BATTERY PERFORMANCE DATA
                       Week ending 26 December 1997

     20 Dec 1997 - GMT Day 354 Beta =  8.3 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/-4.62   +0.0/ +0.0   18.7    0.000     0.0
2   +39.2/ -22.4  +5.47/+4.51  +32.0/-13.6   25.6    1.024    21.6
3  +112.0/  +0.0  +3.87/+2.92  +30.4/-15.2   25.6    1.021    20.9

     26 Dec 1997 - GMT Day 360 Beta = 26.2 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  -2.42/-3.68   +0.0/ +0.0   18.7    0.000     0.0
2   +44.8/  -5.6  +7.41/+5.79  +32.4/-16.0   24.6    1.023    23.6
3   +44.8/ -11.2  +6.11/+4.51  +31.6/-16.8   24.6    1.024    22.9


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

_______________________________________________________________
                         APPENDIX E
                    UARS ANOMALY REPORTS
                Week ending 26 December 1997

  AR NO.   SUBSYS   ORBIT     TIME       TTR         PROBLEM/DATA LOSS
  ------   ------   -----     ----       ---         -----------------
  97-124    FOT     34310   355/2028    14170     Generic Late Acquisition
  97-124    FOT     34350   358/1238    14170     Generic Late Acquisition

ANOMALY CLOSURE INFORMATION RECEIVED
  AR NO.   SUBSYS   ORBIT     TIME       TTR         PROBLEM/DATA LOSS
  ------   ------   -----     ----       ---         -----------------
  97-126    FOT     34104   342/0231              TAC CRASH



 ANOMALY INVESTIGATION REPORTS GENERATED
  AIR NO.  SUBSYS   ORBIT     TIME       TTR      PROBLEM/DATA LOS
-------  ------   -----     ----       ---      -------------
 None this report period