UARS Weekly Status Report

20 July 2001




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                UARS WEEKLY STATUS REPORT - 20 JUL 2001

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

SOLSTICE continues to operate normally, taking solar data on all available
orbital tracking periods and stellar calibration observations whenever
possible. We continue to gather enough data to meet all the SOLSTICE
science objectives during this period of reduced tape recorder operations.

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

SUSIM had a commanding error which caused it to miss two MgII index
scans.  This now has been corrected.  Otherwise, SUSIM has completed
its daily solar scans this past week during periods of predicted UARS
telemetry.

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

Following a loss of power in early May, the ACRIM instrument has not 
responded to power-up commands. The ACRIM team is working on a scenario of 
power-ups and downs to test the apparent inability of the instrument power 
supply to activate.

The ACRIM2 total solar irradiance database has been re-processed and is 
complete up to the May 2001 power loss. The new processing scheme utilizes 
improved algorithms developed for the ACRIMSAT/ACRIM3 experiment whose 
science mission began in April 2000. Reprocessing has found additional 
results and more degradation comparisons that have resulted in a much 
improved version of the total solar irradiance results from the experiment. 
These results are available at the ACRIM Science Team web site 
(http://acrim.com) and at NASA's LaRC and GSFC DAAC's.

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

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

     The PEM team reports that the PEM:: node computer has failed and has
been taken off line.  PEM:: appears to have hardware problems that take the 
system down every few hours.  Automatic transfer NRT tests to PEM2K from
both CDHF2 and CDHFB have succeed and the NRT files have been verified against 
those captured by PEM, which confirm the NRT process is correct.  Thus, PEM 
confirms NRT data from CDHFB.  Thanks to Steve Bove for his work assisting 
PEM with this process.

     PEM/AXIS was activated in activated in full power mode on July 3.  At 
the current time, AXIS is not generating energy deposition.  SwRI is looking 
into this.  Tests of AXIS production code on the rehost computer are continuing.

     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).

    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 
***********

Nothing received.

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

Nothing received.

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

Nothing received.

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

Nothing received.

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

On 17 July 2001 the MPG participated in the biweeekly 
three-TDRS meeting.  These biweekly meetings are 
being held to monitor the development of software
needed to allow UARS to begin using three TDRS 
satellites for commanding and data acquistion.

Daily processing of instrument Daily Activity Plans 
continues with no problems.

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

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

This report covers 07 July 2001 (Orbit 53686, GMT Day 188) through 13 July 2001 
(Orbit 53790, GMT Day 194).

                        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        194/0047     53776     Power OFF
         WINDII       194/0643     53780     Power ON


The beta angle ranged between the angles of 33.7 degrees to 59.0 degrees for 
this report period.  The beta angle is now increasing towards a maximum angle 
of 78 degrees on 20 July 2001 (DOY 201).

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 1.6 degrees C.  Additional battery performance data for each 
battery on 6 July 2001 and 13 July 2001 are provided in Appendix D.

The clock error ranged from Ð11.8 to 10.5 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            =  19
¥     HALOE          =  01
¥     WINDII         =  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:  01/119  - 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 01/193 show the observatory data loss to be 302 hours, 44 
minutes, 57.624 seconds. This shows a zero loss since the last report period. 
This is a 0.39 percent data loss, which equals a 99.61 percent data capture for 
the mission.

                     OTHER SIGNIFICANT EVENTS

                     UARS SATELLITE OPERATIONS

An instrument anomaly was experienced on 05 May 2001.  The instrument involved 
was the ACRIM II instrument.  All ACRIM telemetry for currents and voltages all 
dropped to zero values suddenly.  The ACRIM team in coordination with the 
UARSFOT conducted analysis and command tests to determine the cause of the 
anomaly.  Analysis shows that the anomaly was caused by failed circuitry in the 
ACRIM electronics box.  The FOT is awaiting a future plan of action from the 
ACRIM team.

The software test team, in conjunction with the FOT, has completed a large 
portion of the testing for the new front end processor.  The new TAC still has 
yet to undergo DSN and realtime TDRS testing, but has completed simulations of 
receipt of telemetry, commanding, and NCC/GCMR testing.  DSN testing is 
scheduled for 18 July 2001.

UARSFOT will also begin supporting testing of the rehosted UARS ground system.  
A prototype system has been built in accordance with the UARS documentation and 
operational database.  The demo of the prototype system will be held on 02 
August 2001

UARS attitude has been adjusted over the course of the last few yaw cycles by 
loading new alignment matrices for the TAM.  Good alignments have been found 
for both directions of flight and the performance of the TAM should remain 
stable and accurate. 


                             MEETINGS

The FOT held the UARS Three TDRS Kickoff Meeting on 03 July 2001.  This meeting 
was established to track the progress and resolve problems of all entities 
involved in the implementation of the three TDRS mode.  This meeting will 
become a biweekly meeting until the three TDRS mode is operational.


                    FUTURE SIGNIFICANT EVENTS

The next UARS Yaw slew is scheduled for 08 August 2001 (DOY 220).  This 
maneuver will be a Forward to Reverse 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 13 July 2001

ORBIT     AOS          NO.        SUBSYS     REASON
-----     ---          ---        ------     ------
53690     188/0740     01-445     NBTR       NOOPS D-188
53697     188/1759     01-446     NBTR       NOOPS D-189
53704     189/0600     01-446     NBTR       NOOPS D-189
53711     189/1650     01-446     NBTR       NOOPS D-189
53712     189/1800     01-447     NBTR       NOOPS D-190
53719     190/0600     01-447     NBTR       NOOPS D-190
53727     190/1801     01-447     NBTR       NOOPS D-190
53727     190/1801     01-448     NBTR       NOOPS D-191
53729     190/2120     01-449     OBC/CLK    Clk Adj 0.0 to 20.6 msec/day
53740     191/1506     01-450     OBC        TAM Alignment
53742     191/1801     01-448     NBTR       NOOPS D-191
53750     192/0741     01-451     NBTR       NOOPS D-192
53753     192/1143     01-451     NBTR       PLAYBACK/ /RTS-58
53753     192/1143     01-452     OBC/CLK    Clk Adj 20.6 to 0.0 msec/day
53756     192/1620     01-454     TAM        TAM ALIGNMENT
53757     192/1802     01-453     NBTR       NOOPS D-193
53765     193/0642     01-453     NBTR       NOOPS D-453
53776     194/0047     01-455     HALOE      Power OFF
53780     194/0643     01-456     WINDII     Power ON
53782     194/1005     01-457     OBC        Clk Adj  0.0 to 20.6 msec/day
53785     194/1438     01-458     OBC        TAM Alignment

______________________________________________________________________________

                            APPENDIX B
                  OUT-OF-LIMITS & ALERTS OCCURRENCES
                       Week ending 13 July 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 13 July 2001

                 CLOCK DRIFT RATE ADJUSTMENTS

ORBIT     TIME         CLOCK RATE CHANGE
-----     -----        -----------------
53729     190/2128     Clk Adj 0.0 to 20.6 msec/day
53753     192/1150     Clk Adj 20.6 to 0.0 msec/day
53782     194/1008     Clk Adj  0.0 to 20.6 msec/day

_______________________________________________________________________________

                            APPENDIX D
                  UARS BATTERY PERFORMANCE DATA
                     Week ending 13 July 2001


     6 July 2001 - GMT Day 187 Beta = 29.3 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/-4.31  +0.0/+0.0      12.0      0.000     0.0
2    +11.2/-134.4    +5.79/+4.51  +28.4/-14.4    24.8      1.030     20.7
3    +22.4/-56.0     +4.83/+3.23  +28.0/-15.2    24.8      1.020     20.7


     13 July 2001 - GMT Day 194 Beta = 59.0 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   -3.68/-4.94  +0.0/+0.0      12.0      0.000      0.0
2    +11.2/-33.6     +3.87/+2.60  +22.4/-14.4    26.4      1.030      18.5
3    +22.4/-22.4     +2.92/+1.66  +21.6/-14.4    26.4      1.020      18.0


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

_______________________________________________________________________________

                           APPENDIX E
                      UARS ANOMALY REPORTS
                    Week ending 13 July 2001

                   NEW ANOMALY REPORTS GENERATED
AR NO.   SUBSYS    ORBIT     TIME       TTR      PROBLEM/DATA LOSS
------   ------    -----     ----       ---      -----------------
01-042   FOT       53697   188/1759Z    N/A     Data dropouts/NISN router switch
01-043   FOT       53722   190/0920Z    23951   6 Second TLM dropout at WS


                 ANOMALY CLOSURE INFORMATION RECEIVED
AR NO.   SUBSYS    ORBIT    TIME        TTR      PROBLEM/DATA LOSS
------   ------    -----    ----        ---      -----------------
01-042   FOT       53697    188/1759Z   N/A     Data dropouts/NISN router switch
01-043   FOT       53722    190/0920Z   23951   6 Second TLM dropout at WS


                 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
------     ------     -----     ----        ---      -----------------
01-041     FOT        see list  July 01     14170    Generic Late Acquisition

	 	SEVNTFW01/28