UARS Weekly Status Report

16 JULY 1999




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                UARS WEEKLY STATUS REPORT - 16 JUL 1999

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

SOLSTICE continues to operate normally, collecting solar data on all 
available orbital tracking periods and stellar calibration observations, 
whenever possible.

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

SUSIM's operations this past week have been normal, without apparent 
problems.  Evaluation of the recently reprocessed V20 products before 
their release to the DAAC continues.

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

Nothing received.

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

Nothing received.

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HALOE 
***********

Nothing received.

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

Nothing received.

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

HRDI is operating normally.  A paper will be presented at next week's SPIE
meeting discussing the long-term HRDI performance.

***********
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
***********

UARS PCG received word from the LZP that the data gap for UARS DAY 2849,
30-JUN-1999 @13:21:47 - 14:02:28 is unrecoverable.  Version 2, Cycle 1
is the "Best Available".  All PI Software Reps have been notified.  
                              
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.
        17 days CLA (7.0)  PROD (L1-L3)         (473R-106C-11F=356L)
        51 days WIN (5.11) PROD (L1-L3)         (1540R-945C-8F=587L)
     
UARS PCG will load May 1999 current day DAAC data in July 1999.
                    
CDHF pending software upgrades:  DEC AXP Fortran 6.5, DEC AXP OPEN
VMS 6.2, OpenIngres. 

***********
FOT
***********


REPORTING PERIOD


This report covers 03 July 1999 (Orbit 42668, GMT Day 184) through 09 July 
1999 (GMT Day 190).


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     184/0018     42688     Off
                   PEM        186/2248     42712     AXIS Off
                   HALOE      187/2250     42727     Off

The beta angle ranged between the angles of 26.0 degrees to 5.1 degrees for 
this report period.  The beta angle is now decreasing toward a minimum 
angle of 2.0 degrees on 10 July 1999 (DOY 191).

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 0.8 to 1.0 degrees C.  Additional battery performance data 
for each battery on 02 July 1999 and 09 July 1999 are provided in Appendix 
D.

The clock error ranged from -9.4 to -2.1 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 =     00

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

%     WINDII    01
%     PEM       01
%     HALOE     01


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

%     FOT     03

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

TRANSPONDER FREQUENCIES:
          Transponder A:  99/179  -  2287.496941
          Transponder B:  99/180  -  2287.498977


GROUND SYSTEM OPERATION

Three (3) operational support problem 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 99/189 show the observatory data loss to be 
24 hours, 53 minutes, 59.476 seconds (an increase of 2.432 seconds since 
the last report period).  This is a 0.0364 percent data loss which equals a 
99.9636 percent data capture for the mission.

The increase of 2.432 seconds occurred over two (2) day:

7 2.048 seconds on Day 183 due to data hits,
7 0.384 seconds on Day 188 due to a data hit.


OTHER SIGNIFICANT EVENTS

UARS SATELLITE OPERATIONS

FOT personnel are supporting the IMOC (SCS-21) development effort.  The 
current work is a continuation of the SCS-21 UARS implementation effort 
done last year which culminated in a level 1 demonstration.

The FOT continues to investigate the feasibility of a new PMON action to 
change battery V/T curves based on loading to mitigate battery risks in sun 
pointing safehold.

YEAR 2000 OPERABILITY SUPPORT

The end-to-end testing has been delayed until a new FORMATS software 
release can be made to accommodate the special Y2K planning aids.


MEETINGS

The FOT attended the 1999 Leonid Meteor Storm Presentation on 08 July 1999. 


FUTURE SIGNIFICANT EVENTS

The next UARS Yaw Around Maneuver (reverse-to-forward) is scheduled for 10 
July 1999 (DOY 191).


PERSONNEL CHANGES

None

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 09 July 1999

ORBIT        AOS         NO.     SUBSYS      REASON
-----        ---         ---     ------   -------  
42668     184/0018     99-235   WINDII     Power OFF, EON LBV 23.6
42712     186/2248     99-236   PEM        AXIS Power OFF
42727     187/2250     99-237   HALOE      Power OFF

_______________________________________________________________

                              APPENDIX B
                  OUT-OF-LIMITS & ALERTS OCCURRENCES
                        Week ending 09 July 1999

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 09 July 1999

                      CLOCK DRIFT RATE ADJUSTMENTS

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


                              APPENDIX D
                    UARS BATTERY PERFORMANCE DATA
                        Week ending 09 July 1999


     02 July 1999 - GMT Day 183 Beta = 26.0 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  -100.8/-123.2  -3.05/-4.31  +0.0/ +0.0    16.5    0.000    0.0
2   +11.2/-72.8   +6.11/+4.51 +29.6/-16.0    23.8    1.023   21.5
3   +22.4/-56.0   +5.15/+3.87 +28.8/-15.6    23.7    1.020   21.2


     09 July 1999 - GMT Day 190 Beta = 5.1 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  -100.8/-123.2 -3.05/-4.31   +0.0/+0.0     16.5    0.000    0.0
2   +33.6/-22.4  +5.47/+4.51  +30.0/-13.6    24.6    1.015   21.4
3   +50.4/-5.6   +4.51/+3.55  +29.6/-14.4    24.5    1.016   21.1


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



                              APPENDIX E
                         UARS ANOMALY REPORTS
                        Week ending 09 July 1999


                    NEW ANOMALY REPORTS GENERATED
  AR NO.   SUBSYS    ORBIT      TIME       TTR      PROBLEM/DATA LOSS
  ------   ------    -----      ----       ---      -----------------
99-033     FOT       42686     185/0518   14170    Generic Late Acquisition
99-033     FOT       42761     190/0450   14170    Generic Late Acquisition
99-033     FOT       42771     190/2118   14170    Generic Late Acquisition


                ANOMALY CLOSURE INFORMATION RECEIVED
  AR NO.   SUBSYS    ORBIT      TIME       TTR      PROBLEM/DATA LOSS
  ------   ------    -----      ----       ---      -----------------
99-031    FOT        42629    181/1033    21028     NEG ACQ. 15:00 RECOV.
99-032    FOT        42629    181/1220    21028     NEG ACQ 00:41:04 LOST


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


                        OPEN ANOMALY REPORTS
  AR NO.   SUBSYS    ORBIT      TIME       TTR      PROBLEM/DATA LOSS
  ------   ------    -----      ----       ---      -----------------
99-033     FOT     see list     July 99    14170    Generic Late Acq.

	 	SEVNTFW99/28