UARS Weekly Status Report

29 June 2001




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                UARS WEEKLY STATUS REPORT - 29 JUN 2001

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

SOLSTICE began day only operations on day 178 (6/27) in support of the yaw
maneuver. We were subsequently turned offcompletely on day 179 due to low
power conditions during the yaw. We expect to return to normal operations
on day 182. Otherwise, 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
***********

Nothing received.

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

Nothing received.

***********
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 have 
succeed however the NRT files have to be verified against those captured by
PEM to confirm the NRT process is correct.

     PEM/AXIS was activated in its half power mode on June 24.  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.
***********
HALOE 
***********

Nothing received.

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

Nothing received.

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

Nothing received.

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

Nothing received.

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

On 27 June 2001 the MPG participated in the UARS Monthly 
Status Review Meeting.  Normally, these meetings are 
held on the first Wednesday of each month.  Since the 
first Wednesday of July is a holiday, this meeting was
moved to the last week of June. Daily processing of 
instrument Daily Activity Plans continues with no problems.

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

Following one week of parallel operations between the
UARS CHDF legacy system and the Rehost system that began on June 18, the
operational transition to production processing on the Rehost system
occurred on June 25.  The NRT data flow remains on the legacy system and
will be moved to the Rehost system during the week of July 9.  The NRT was
not moved earlier due to the planned yaw maneuver on June 28 and other test
activities and the holiday during the week of July 2. 
                  
***********
FOT
***********

                          REPORTING PERIOD

This report covers 16 June 2001 (Orbit 53371, GMT Day 167) through 22 June 2001 
(Orbit 53475, GMT Day 173).

                       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
          WINDII        169/0403      53403      Power OFF (S/C Low Power)
          HALOE         172/1424      53454      Power OFF
          HALOE         172/1745      53456      Power ON
          SOLSTICE      172/1827      53457      Power ON
          ACRIM         172/1827      53457      Power ON
          SUSIM         172/1928      53457      Power ON
          SUSIM         172/2145      53459      Power ON
          HRDI          173/0225      53462      Power ON


The beta angle ranged between the angles of 32.8 degrees to 21.7 degrees for 
this report period.  The beta angle is now decreasing towards a minimum angle 
of 0 degrees on 28 June 2001 (DOY 179).

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 1.3 to 1.6 degrees C.  Additional battery performance data for each 
battery on 15 June 2001 and 22 June 2001 are provided in Appendix D.

The clock error ranged from Ð11.8 to 10.3 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   =  13
¥      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
¥      WINDII          =  01
¥      HALOE           =  02
¥      SOLSTICE        =  01
¥      ACRIM           =  01
¥      SUSIM           =  02
¥      HRDI            =  01

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

¥      FOT             =  02

One (1) Anomaly Reports 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 01/158 show the observatory data loss to be 301 hours, 02 
minutes, 12.728 seconds. This shows 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

The FOT continues to fine-tune the TAM alignment by loading new alignment 
matrices. A new alignment is required for the reverse flight direction.  This 
is a slow process and it will take many alignments to lock in on the most 
accurate solution.

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 is conducting analysis and command tests to determine the cause of the 
anomaly.  Analysis shows that the anomaly was caused due to failed circuitry in 
the ACRIM electronics box.  The FOT is awaiting a future plan of action from 
the ACRIM team.


                              MEETINGS

The FOT attended a UARS SERB/TAC RS Meeting on Wednesday, June 20, 2001.

                     FUTURE SIGNIFICANT EVENTS

The next UARS Yaw slew is scheduled for 28 June 2001 (DOY 179).  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 22 June 2001

ORBIT      AOS          NO.        SUBSYS      REASON
-----      ---          ---        ------      ------
53373      167/0440     01-393     NBTR        NOOPS D-167
53381      167/1742     01-393     NBTR        NOOPS D-167
53382      167/1824     01-395     NBTR        NOOPS D-168
53389      168/0540     01-395     NBTR        NOOPS D-168
53396      168/1742     01-396     NBTR        NOOPS D-169
53403      169/0403     01-397     WINDII      Power OFF (S/C Low Power)
53404      169/0539     01-396     NBTR        NOOPS D-169
53405      169/0720     01-398     OBC         Clk Adj fr 0.00 to 20.6 msec/day
53411      169/1743     01-396     NBTR        NOOPS D-169
53412      169/1825     01-399     NBTR        NOOPS D-170
53419      170/0540     01-399     NBTR        NOOPS D170
53421      170/0908     01-400     OBC         Clk Adj fr 20.6 to 0.00 msec/day
53426      170/1743     01-399     NBTR        NOOPS D170
53433      171/0443     01-401     NBTR        NOOPS D171
53442      171/1826     01-402     NBTR        NOOPS D172
53449      172/0626     01-402     NBTR        NOOPS D172
53454      172/1424     01-403     HALOE       Power OFF
53456      172/1745     01-405     HALOE       Power ON
53457      172/1827     01-406     SOLSTICE    Power ON
53457      172/1827     01-407     ACRIM       Power ON
53457      172/1827     01-404     NBTR        NOOPS D173
53457      172/1928     01-408     SUSIM       Power ON
53459      172/2145     01-409     SUSIM       Power ON
53462      173/0225     01-410     HRDI        Power ON
53463      173/0445     01-411     OBC         Clk Adj fr 0.0 to -20.6 msec/day
53464      173/0627     01-404     NBTR        NOOPS D173
53472      173/1746     01-412     NBTR        NOOPS D174
______________________________________________________________________________

                            APPENDIX B
               OUT-OF-LIMITS & ALERTS OCCURRENCES
                    Week ending 22 June 2001

The following Out-Of-Limits occurrences were detected:

MNEMONIC       STATE     DESCRIPTION                     ORBITS
--------       -----     -----------                     ------
WIQBVOLTAGE    Y-LO      WINDII Quiet Bus Voltage        53373-6
HRPSEQBIMON    Y-HI      PSE Quiet Bus Current Monitor   53373-6
WIQBVOLTAGE    Y-LO      WINDII Quiet Bus Voltage        53387-90
HRPSEQBIMON    Y-HI      PSE Quiet Bus Current Monitor   53388-90
CDUNRG28       Y-LO      +28 UNREG Bus                   53388-90
WIQBVOLTAGE    Y-LO      WINDII Quiet Bus Voltage        53402-3
HRPSEQBIMON    Y-HI      PSE Quiet Bus Current Monitor   53402-3
PWLBV          Y-LO      Load Bus Voltage                53402-3
PWBAT3V        Y-LO      Battery 3 Voltage               53402-3
CDUNRG28       Y-LO      +28 UNREG Bus                   53402-3
PWLBV          Y-LO      Load Bus Voltage                53402-3
PWBAT2V        Y-LO      Battery 2 Voltage               53454
PWBAT3V        Y-LO      Battery 3 Voltage               53454


The following ALERT occurrences were detected:

MNEMONIC      DESCRIPTION      ORBITS
--------      -----------      ------
-None this report period

_______________________________________________________________________________

                            APPENDIX C
               CLOCK & SOLAR ARRAY RATE CORRECTIONS
                    Week ending 22 June 2001
 
                   CLOCK DRIFT RATE ADJUSTMENTS

ORBIT      TIME          CLOCK RATE CHANGE
-----      -----         -----------------
53405      169/0723      Clk Adj fr 0.00 to 20.6 msec/day
53421      170/0911      Clk Adj fr 20.6 to 0.00 msec/day
53463      173/0449      Clk Adj fr 0.0 to -20.6 msec/day

_______________________________________________________________________________

                           APPENDIX D
                  UARS BATTERY PERFORMANCE DATA
                     Week ending 22 June 2001


      15 June 2001 - GMT Day 166 Beta = 33.4 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/-78.4      +6.44/+4.51  +28.4/-15.2   23.8     1.030     20.2
3    +16.8/-89.6      +5.15/+3.55  +28.0/-15.2   23.8     1.020     19.9


      22 June 2001 - GMT Day 173 Beta = 21.7 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/-112.0     +5.79/+4.51  +28.8/-14.4   24.5      1.040     20.8
3     +22.4/-56.0      +4.83/+3.23  +28.4/-14.4   24.3      1.040     20.5


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

                           APPENDIX E
                      UARS ANOMALY REPORTS
                     Week ending 08 June 2001

                   NEW ANOMALY REPORTS GENERATED
AR NO.      SUBSYS      ORBIT      TIME        TTR      PROBLEM/DATA LOSS
------      ------      -----      ----        ---      -----------------
01-032      FOT         53437      171/0947    14170    Generic Late Acquisition
01-038      FOT         53454      172/1424    N/A      TMON 1, 2 TRIPPED


                 ANOMALY CLOSURE INFORMATION RECEIVED
AR NO.      SUBSYS      ORBIT      TIME        TTR      PROBLEM/DATA LOSS
------      ------      -----      ----        ---      -----------------
01-033      FOT         53222      157/0220     N/A  CDEL function not working
01-034      FOT         53225      157/0754     N/A     Unable to dump ATC
01-037      FOT         53292      161/1820     N/A     Unable to load ATC
01-038      FOT         53454      172/1424     N/A     TMON 1, 2 TRIPPED


                  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
------      ------      -----      ----         ---      -----------------
01-032      FOT      see list      June 01      14170  Generic Late Acquisitio
	 	SEVNTFW01/25