UARS Weekly Status Report

06 AUGUST 1999




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                UARS WEEKLY STATUS REPORT - 06 AUG 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 gathered its normal solar, offset, and occultation data this past
week without apparent problems.

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

Nothing received.

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

Nothing received.

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

Nothing received.

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

Nothing received.

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

HRDI is operating normally.

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

WINDII is next scheduled for activation August 12-15, 1999.
Gordon Shepherd gave two WINDII presentations at the IUGG
meeting in Birmingham, U.K., July 19 - July 30.  

***********
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. 

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

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.
        16 days CLA (7.0)  PROD (L1-L3)         (473R-158C-12F=303L)
        11 days GPI (4.05) PROD (CLAES L3B)     (69R-45C=24L)
         9 days WIN (5.11) PROD (L1-L3)         (1540R-1028C-33F=479L)

The CDHF completed the upgrade of Multinet to V4.2 as part of
the ongoing Y2K implementation effort.  

Additional ISO compliant procedures for the new Alpha 4000's 
(CDHFA/B - REHOST) are currently being drafted. These additions
reflect the new Storage Silo (HSM). Current CDHF User interfaces,
menus etc., will not change.
     
DAAC data created in the month of May 1999 has been loaded into the 
DAAC transfer tables for HALOE, PEM, NMC, and UK

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

REPORTING PERIOD


This report covers 24 July 1999 (Orbit 42983, GMT Day 205) through 30 July 1999
(GMT Day 211).
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        206/0725     43002     Off
              ACRIM        207/0013     43012     On
              SUSIM        207/0013     43012     On
              WINDII       207/0909     43018     On
              MLS          208/2342     43042     Off
              WINDII       209/2257     43056     Off

The beta angle ranged between the angles of 50.4 degrees to 74.1 degrees for 
this report period.  The beta angle is now increasing toward a maximum angle of 
75 degrees on 31 July 1999 (DOY 212).

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 0.8 degrees C.  Additional battery performance data for each 
battery on 23 July 1999 and 30 July 1999 are provided in Appendix D.

The clock error ranged from -11.0 to 11.2 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  =   03

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

%     FOT     =   04
%     WINDII  =   02
%     MLS     =   02
%     HRDI    =   02
%     HALOE   =   01
%     ACRIM   =   01
%     SUSIM   =   01

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

%     FOT     =   05

Four (4) 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

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 99/210 show the observatory data loss to be 24 hours, 54 
minutes, 39.732 seconds (an increase of 1.088 seconds since the last report 
period).  This is a 0.0362 percent data loss which equals a 99.9638 percent 
data capture for the mission.

The increase of 1.088 seconds occurred over one (1) day:

7 1.088 seconds on Day 206 due to no overlap.


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 FOT received a set of Y2K planning aids from FDF which will be used to 
facilitate UARS Y2K end-to-end testing.  Eleven 3-day planning aid files were 
received and processed by the FOT.  Two of these files did not process 
successful on the CMS due to either incorrect data, or invalid data formats.  
FDF has been notified of the problems, and are in the process of correcting the 
files.


MEETINGS

None.


FUTURE SIGNIFICANT EVENTS

August 20, 1999 (DOY 232): The next UARS Yaw Around Maneuver (forward-to 
reverse) is scheduled.

Aug 11, 1999 (DOY 223): Preparations for an eclipse of the Sun is planned.  All 
instruments will be scheduled off.  Final details will be available next week.

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 30 July 1999

ORBIT        AOS         NO.      SUBSYS     REASON
-----        ---        ---       ------     -------  
42995     205/2008     99-252     MLS        SCAN RESET
43002     206/0725     99-253     HALOE      Power OFF
43011     206/2242     99-254     OBC        Clk Adj 20.6 to 0.00 msec/day
43012     207/0013     99-255     ACRIM      Power ON
43012     207/0013     99-256     SUSIM      Power ON
43018     207/0909     99-257     WINDII     Power ON
43027     207/2338     99-258     OBC        Clk Adj 0.00 to 20.6 msec/day
43033     208/0909     99-259     OBC        Clk Adj 20.6 to 41.2 msec/day
43039     208/1850     99-260     HRDI       HRDI BARREL
43042     208/2342     99-261     MLS        Power OFF
43052     209/1531     99-262     HRDI       HRDI MPL
43056     209/2257     99-263     WINDII     Power OFF
43067     210/1532     99-264     OBC        Clk Adj fr 41.2 TO 20.6 msec/day

_______________________________________________________________

                       APPENDIX B
             OUT-OF-LIMITS & ALERTS OCCURRENCES
                  Week ending 30 July 1999

MNEMONIC       STATE     DESCRIPTION          ORBITS
---------      -----     ------------         ------
HRPTSBARTMP     Y-LO     HRDI BARREL TEMP     CONTINUOUS
HRPTSBARTMP     Y-HI     HRDI BARREL TEMP     43043-45
HRPTSBARTMP     R-HI     HRDI BARREL TEMP     43046-56


The following ALERT occurrences were detected:

MNEMONIC                 DESCRIPTION         ORBITS
---------               ------------         ------
       No Alerts to report this report period.

_______________________________________________________________

                      APPENDIX C
          CLOCK & SOLAR ARRAY RATE CORRECTIONS
                Week ending 30 July 1999

              CLOCK DRIFT RATE ADJUSTMENTS

ORBIT
TIME
CLOCK RATE CHANGE

43011
206/22:52 (25 July 99)
from 20.6 to 00.0 msec/day

43027
207/23:44 (26 July 99)
from 00.0 to 20.6 msec/day

43033
208/09:15 (27 July 99)
from 20.6 to 41.2 msec/day

43067
210/15:35 (29 July 99)
from 41.2 to 20.6 msec/day




                       APPENDIX D
            UARS BATTERY PERFORMANCE DATA
               Week ending 30 July 1999

     23 July 1999 - GMT Day 204 Beta = 50.4 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  -106.4/-134.4 -3.05/-4.62   +0.0/+0.0      16.5     0.000       0.0
2   +44.8/-22.4  +5.47/+4.19  +26.4/-16.0     25.1     1.021      21.0
3   +22.4/-50.4  +4.51/+3.23  +25.6/-15.6     25.0     1.023      20.7


     30 July 1999 - GMT Day 211 Beta = 74.1 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   -112.0/-134.4  -2.42/-3.68  +0.0/+0.0     16.5     0.000       0.0
2    +22.4/-5.6    +2.60/+1.66 +16.4/-13.6    27.5     1.036      13.4
3    +22.4/-22.4   +1.97/+1.03 +16.0/-13.6    27.5     1.035      13.1


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



                         APPENDIX E
                    UARS ANOMALY REPORTS
                  Week ending 30 July 1999


               NEW ANOMALY REPORTS GENERATED
AR NO.     SUBSYS     ORBIT      TIME     TTR     PROBLEM/DATA LOSS
------     ------     -----      ----     ---     -----------------
99-035     FOT        43006     206/1331          TAC Crashed
99-033     FOT        43030     208/0456  14170   Generic Late Acquisition
99-033     FOT        43032     208/0731  14170   Generic Late Acquisition
99-036     FOT        43050     209/1222          TAC Crashed
99-037     FOT        43055     209/2020          TAC Crashed


         ANOMALY CLOSURE INFORMATION RECEIVED
AR NO.     SUBSYS     ORBIT     TIME     TTR     PROBLEM/DATA LOSS
------     ------     -----     ----     ---     -----------------
                 None this report period


        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
------     ------     -----     ----     ---     -----------------
99-033     FOT     see list   July 99    14170  Generic Late Acq.
99-035     FOT     43006      206/1331          TAC Crashed
99-036     FOT     43050      209/1222          TAC Crashed
99-037     FOT     43055      209/2020          TAC Crashed

	 	SEVNTFW99/31