UARS Weekly Status Report

27 October 2000




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                UARS WEEKLY STATUS REPORT - 27 OCT 2000

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

This week SOLSTICE supported the low spacecraft power condition during the
yaw maneuver by powering off during orbit eclipse and taking data only on
the daylit side of each orbit. Normal operations resumed on day 299. 

SOLSTICE is in good health, collecting solar data on all available orbital
tracking periods and stellar calibration observations whenever possible.
Our solar data is not affected by the larger than normal pointing errors
since they are within our calibrations.

Additionally, we continue to gather enough data to meet all the SOLSTICE
science objectives during this period of reduced tape recorder operations.
However, level2 processing is halted due to deficiencies in the OA_SSPP_ATT
service. CDHF and CSC personnel are working on the problem and plan to have
a patch released by today (Oct 27).

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

SUSIM turned off for the yaw-around on 10/21/00 and was turned back on
and resumed taking data on 10/25/00.  Otherwise, it continues to gather
a normal set of daily solar scans scheduled for predicted periods of
UARS telemetry.

We are preparing to begin the reprocessing the SUSIM UV spectral
irradiances to data version V21 in the next few weeks.

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

Nothing received.

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

     The PEM zenith spectrometers are activate in daylight mode.

     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 
***********

HALOE was powered beginning-of-day today.  All engineering parameters are
within nominal operating region.  Gain and bore sight verification tests
will be conducted over the beta cycle.

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

Nothing received.

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

Nothing received.

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

Nothing received.

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

The daily processing of instrument Daily Activity Plans continues
with no problems.  Instrument operations schedule is complete to
3 December 2000.  The MPG continues to coordinate with the Flight
Operations Team and to assist the Project Scientist with the
scheduling of instrument operations.
 
***********
CDHF
***********

HIGHLIGHTS
----------
o  UOAS (Solstice requested) delivery should be received at the CDHF sometime
   next week. We will notified all PI SW reps with release notes.
o  UARS PCG continue to notify PI Software Representatives regarding Data Gaps
   that occur in the LEVEL0 data due to the UARS Spacecraft Anomaly.

o  DAAC DATA: 
   -  MLS Version 5 data is being previewed and loaded into the DAAC Transfer
      Tables.  Updating of various fields (per 5 day profile) in the DAAC Tables
      that are needed to meet DAAC criteria have been done. We are verifying. 
      Additional updating appears to be required to reflect north/south
      variations in min /max lat values. DAAC (James Johnson) has been
      notified when to load. 
 
   -  WINDII requested Version 11 be sent to the DAAC from start of mission to
      31-Aug-1997.  WINDII needs to update the UARS_QUALITY field.  Currently
      waiting response from WINDII that the fields have been updated.  DAAC
      will be notified.
            
o  UARS CDHF REHOST:
   -  SUSIM v7.2 software representative Ed Esfandiari notified parallel
      testing completed.  *SUSIM responded with concerns regarding the output
      product which is being investigated.
   -  HRDI v4.4 software representative Jim Raines was notified parallel
      testing completed. HRDI has responded.       
   -  GPI V4.05 tested successfully against the HRDI V4.4 Level 3AL data.
      Frank Huang was requested to validate the GPI output product.  *Frank
      responded with questions and some concerns.     
   -  SOLSTICE v4.62 software representative PI Barry Knapp has successfully
      validated the parallel testing output.  
   -  HALOE v4.82 software representative Lance Deaver was notified the
      parallel test days completed.  *HALOE has responded that they see no major
      differences in the output product, but have 3 more species to check out.
      Currently waiting response.     
   -  WINDII V5.11A software representative Brian Solheim was notified the
      parallel test days are complete.  WINDII will be requested to validate
      the output product and compare against same days processed on current
      system.
   -  PEM is ready to run.           
                  
***********
FOT
***********

                              REPORTING PERIOD

This report covers 14 October 2000 (Orbit 49697, GMT Day 288) through 20 
October 2000 (Orbit 49801, GMT Day 294).

                            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
             WINDII       290/2349     49741     Off
             HALOE        292/2354     49771     Off
             PEM          294/2317     49800     Off

The beta angle ranged between the angles of 34.7 degrees to 8.9 degrees for 
this report period.  The beta angle is now decreasing toward a minimum angle of 
2 degrees on 23 October 2000 (DOY 297).

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 0.6 to 1.0 degrees C.  Additional battery performance data for each 
battery on 13 October 2000 and 20 October 2000 are provided in Appendix D.

The clock error ranged from -5.2 to 8.3 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  =  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
¥     PEM            =  01

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

¥     FOT            =  05

One (1) Anomaly Reports remained OPEN at the end of this report period (see 
Appendix E).

TRANSPONDER FREQUENCIES:
· Transponder A:  00/221  -  2287.496937
· Transponder B:  00/244  -  2287.499127


                        GROUND SYSTEM OPERATION

Five (5) 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 00/293 show the observatory data loss to be 298 hours, 39 
minutes, 55.664 seconds (an increase of 4 minutes 38.448 seconds since the last 
report period).  This is a 0.39 percent data loss which equals a 99.61 percent 
data capture for the mission.

The increase of 4 minutes 38.448 seconds occurred over one (1) day:

· 4 minutes 38.448 seconds on Day 287 due to late acquisition caused by weather 
conditions at White Sands.

                      OTHER SIGNIFICANT EVENTS

                      UARS SATELLITE OPERATIONS

Testing continues daily to get the TAM and FSS attitude control solution 
operational.  The UARS testing and training simulator (UTTS) is being used for 
all testing.  In order to insure the validity of the test the FOT has been 
debugging some problems with the simulator attitude models.  This week two bad 
bits were found in the FSS data on the simulator.  The FOT is attempting to 
isolate the problem.

The plan for the 23 October 2000 yaw maneuver was made this week.  It was 
decided that for the maneuver the nominal script will be followed with a few 
additions.  The forward and reverse gyro biases will be uplinked before and 
after the maneuver, respectively.  This will be done to hold a proper attitude 
without the FSS.  The FSS will also be put into monitor mode and once the 
residuals show reasonable values the FSS will be put back into update mode.  We 
are confident that this plan will be sufficient to maintain good attitude 
control.  If needed FDF will be standing by to provide support and contingency 
procedures have been generated.  All additions have been verified on the 
simulator.


                                MEETINGS

The FOT attended a meeting to discuss UARS attitude control and yaw maneuver 
plans on 16 and 18 October 2000.


                       FUTURE SIGNIFICANT EVENTS

The next UARS Yaw slew has been rescheduled for October 23, 2000 (DOY 297).  
This maneuver will be a Forward to Reverse Flight maneuver (Northern Hemisphere 
viewing).  The maneuver was delayed so that maximum support from Flight 
Dynamics, CDHF and the FOT would be present should an anomaly occur.

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 20 Oct 2000

ORBIT     AOS         NO.        SUBSYS     REASON
-----     ---         ---        ------     -------
49699     288/0449    00-568     NBTR       NOOPS D-288
49707     288/1747    00-568     NBTR       NOOPS D-288
49707     288/1829    00-569     NBTR       NOOPS D-289
49714     289/0548    00-569     NBTR       NOOPS D-289
49722     289/1750    00-569     NBTR       NOOPS D-289
49722     289/1830    00-570     NBTR       NOOPS D-290
49729     290/0551    00-570     NBTR       NOOPS D-290
49736     290/1652    00-571     OBC        GYRO BIAS
49737     290/1752    00-570     NBTR       NOOPS D-290
49741     290/2349    00-573     WINDII     Power OFF
49748     291/1112    00-572     NBTR       NOOPS D-291
49750     291/1514    00-574     OBC        GYRO BIAS
49752     291/1833    00-575     NBTR       NOOPS D-292
49760     292/0636    00-575     NBTR       NOOPS D-292
49765     292/1516    00-576     OBC        GYRO BIAS
49770     292/2314    00-577     NBTR       NOOPS D-293
49771     292/2354    00-578     HALOE      Power OFF
49775     293/0639    00-577     NBTR       NOOPS D-293
49780     293/1434    00-579     OBC        GYRO BIAS
49782     293/1801    00-577     NBTR       NOOPS D-293
49796     294/1436    00-580     OBC        GYRO BIAS
49800     294/2317    00-581     PEM        Power OFF, HEPS, ZEPS
_______________________________________________________________________________

                               APPENDIX B
                   OUT-OF-LIMITS & ALERTS OCCURRENCES
                        Week ending 20 Oct 2000

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 20 Oct 2000

                       CLOCK DRIFT RATE ADJUSTMENTS

ORBIT     TIME                         CLOCK RATE CHANGE
-----     ----                         -----------------
          -None this report period

___________________________________________________________________________

                               APPENDIX D
                    UARS BATTERY PERFORMANCE DATA
                       Week ending 20 Oct 2000

     13 Oct 2000 - GMT Day 287 Beta = 37.7 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     14.2     0.000     0.0
2    +16.8/-67.2     +5.47/+4.51  +28.8/-15.2   25.0     1.030     21.0
3    +5.6/-140.0     +4.51/+3.23  +28.4/-15.2   25.0     1.030     20.9


     20 Oct 2000 - GMT Day 294 Beta = 12.8 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     14.2      0.000     0.0
2    +22.4/-5.6      +4.51/+3.87  +29.2/-12.8   25.8      1.040     19.4
3    +00.0/-95.2     +3.55/+2.60  +28.4/-12.8   25.8      1.040     19.0


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

                               APPENDIX E
                         UARS ANOMALY REPORTS
                       Week ending 20 Oct 2000

                   NEW ANOMALY REPORTS GENERATED
AR NO.     SUBSYS   ORBIT     TIME       TTR      PROBLEM/DATA LOSS
------     ------   -----     ----       ---      -----------------
00-044     FOT      49715     289/0735   23031    Dropout at WS
00-045     FOT      49719     289/1248   N/A      TAC 6 Crashed
00-042     FOT      49773     293/0414   14170    Generic Late Acq.
00-042     FOT      49776     293/0749   14170    Generic Late Acq.
00-042     FOT      49800     294/2213   14170    Generic Late Acq.

                 ANOMALY CLOSURE INFORMATION RECEIVED
AR NO.     SUBSYS   ORBIT     TIME       TTR      PROBLEM/DATA LOSS
------     ------   -----     ----       ---      -----------------
00-032     FHST     48211     188/2242   N/A      FHST 2 Anomaly
00-040     FOT      48854     231/2111   22831    Data Dropout
00-044     FOT      49715     289/0735   23031    Dropout at WS
00-045     FOT      49719     289/1248   N/A      TAC 6 Crashed

                    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
------     ------    -----     ----      ---      -----------------
00-042     FOT       see list  Oct 00    14170    Generic Late Acq.


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