UARS Weekly Status Report

14 November 1997





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                UARS WEEKLY STATUS REPORT - 14 November 1997

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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 successfully gathered its normal solar, offset, and occultation
scan data during this past week without apparent problems.

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

Nothing received.

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

HALOE was turned on November 11, 1997. On the next pass (TDRS contact) the
end-of night voltage dropped below 24 volts.  The HALOE heater/motor bus
was turned off to reduce the load on the bus.  The main HALOE power bus was
left on and the heater/motor bus was turned back on at approximately 16:00
GMT.  The UARS FOT was very helpful during this process.

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

The MLS instrument has been powered off since Nov 4. MLS is scheduled to
begin north viewing operations on Nov 20.

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

HRDI was turned on 11/13/97.  We are scheduled to be on till 11/19/97.  
Operation is normal.

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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 CDHF Status Week Ending November 14, 1997
---------------------------------------------                             
The software that generates the UARS level 0 files and related NRT and Quicklook
products will be re-hosted to a new hardware platform on Saturday November 15,
1997. UARS CDHF users have been notified about the delay in NRT, Quicklook and
potentially the Level 0 product that will occur on this date. The time
estimate for this re-hosting activity is from 12:00GMT- 17:00GMT Nov. 15.

The CDHF has received a total of 341 CD-ROM requests as of 14 November 97.
One new CD-ROM order was received and shipped this week.

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.           
                  30 days PEM (3.32) Prod (1350R-565C=785L)
                  13 days MLS (4.9) ENG (40R-40C=0L)

The CDHF has previewed the DAAC Transfer Data for September 1997 current day
data.
                                                                    
Pending CDHF software upgrades include IDL 5.0, and OpenIngres 2.0
                  
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FOT
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REPORTING PERIOD

This report covers 31 October 1997 (Orbit 33548, GMT Day 304) through 
07 November 1997 (Orbit 33653, GMT Day 311).


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
     PEM       306/0900     33570     ZEPS Off
     MLS       308/2051     33606     Off

The beta angle reached a minimum angle of 0.0 degrees on 07 November 1997 (DOY
311).  The beta angle is now increasing toward a maximum angle of 78.1 degrees 
on 27 November 1997 (DOY 331).

Version 62B of the On Board Computer (OBC) flight software was successfully 
uplinked on Thursday, 06 November 1997 (310/20:41-20:49 UTC, Orbit 33636). The 
flight software revision corrects minor problems identified during the last 
yaw maneuver (see AIR 97-113).  The revised software functioned flawlessly 
during the yaw maneuver.

A Forward-to-Reverse Yaw Around maneuver (number 63) was successfully executed
in Orbit 33646 at 13:27:11 UTC on 07 November 1997.  The SSPP Instruments 
(ACRIM, SOLSTICE, and SUSIM) were enabled.  Due to the SA position at 269 
degrees, the effective night length of the Spacecraft after the maneuver was 
48 minutes.  Post maneuver analysis of data indicate that during the Yaw 
Around, the end-of-night load bus voltage was 23.2 volts and the average depth 
of discharge (DOD) on both Batteries 2 and 3 was approximately 25.0 percent.

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 23.2 end-of-night (EON) load bus voltage.  Battery 
temperatures are stable with a temperature delta between Battery 2 and Battery
3 of 1.3 degrees C.  Additional battery performance data for each battery on 
01 November 1997 and 07 November 1997 are provided in Appendix D.

The clock error ranged from -11.1 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.

%     ALERTS            =     01
%     OUT-OF-LIMITS     =     15

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

%     FOT      03
%     HRDI     03
%     MLS      02
%     SUSIM    01

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

%     FOT      02

TRANSPONDER FREQUENCIES:
     Transponder A:  97/301 - 2287.497086
     Transponder B:  97/302 - 2287.499098


GROUND SYSTEM OPERATION

One (1) operational support problem(s) 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 97/310 show the observatory data loss to be 20 hours, 41 
minutes, 03.985 seconds (no change).  This is a 0.0385 percent data loss which 
equals a 99.9615 percent data capture for the mission.

No testing of the new CMS software release (R7B1V2) occurred this week.

Investigation of the stored command verification problem - time to complete - 
associated with Applications Processor (AP) software release 10.08 continued.  
The cause has been identified, but rectifying the problem continues.


OTHER SIGNIFICANT EVENTS

Completed testing of the new flight software revision (V62B) on Wednesday, 05 
November 1997.  The flight software revision corrects minor problems identified 
during the last yaw maneuver (see AIR 97-113).

Monitoring of the magnetic field model performance continues.

FOT continues to develop an updated Power Profile for UARS due to the current 
status of the Modular Power System.

FOT continues to support the new UARS ground system re-engineering effort.


MEETINGS

No UARS Battery telecon was held this week.  The next telecon has not been 
scheduled.


FUTURE SIGNIFICANT EVENTS

The next UARS Yaw Around Maneuver is currently scheduled for 17 December 1997 
at 311/132708.

The Replacement Level Zero Processor (LZPR) will be elevated to operational 
status on 15 November 1997.  The replacement procedure will result in a planned
10-hour downtime during which no Level Zero Data will be processed - no Near 
Realtime Data (NRT) or FOT plots.

The UARS Off-Line personnel will relocate to the second floor of Building 32 
adjacent to the UARS/TOMS Mission Operations Room on 10 November 1997.

The UARS orbit altitude is dropping slowly and a drag makeup orbit adjust will 
probably be required in mid-1998.


FACILITIES

CRTs, computers, and other equipment are being installed in the semi-circular 
console within the UARS/TOMS Mission Operations Room (MOR).  Operations 
continue from a dedicated room in the EOS area which is across the hall.


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 07 November 1997

ORBIT        AOS         NO.     SUBSYS             REASON
-----        ---        ---      ------             -------  
33563     305/2223     97-546     HRDI     HRDI HTR DELAY TO 450
33564     306/0114     97-547     HRDI     HRDI HTR DELAY TO 25
33565     306/0252     97-548     MLS      Power ON
33571     306/1220     97-549     HRDI     HRDI HTR DELAY TO 450
33606     308/2051     97-550     MLS      Power OFF
33617     309/1409     97-551     OBC      Clk Adj fr 0.00 to 20.6 msec/day
33634     310/1733     97-552     OBC      Clk Adj fr 20.6 to 0.00 msec/day
33636     310/2039     97-553     OBC      Load patch for skew wheel reversal
                                           problem
33648     311/1540     97-554     SUSIM    Reset sunrise and sunset times


_______________________________________________________________

                              APPENDIX B
                  OUT-OF-LIMITS & ALERTS OCCURRENCES
                       Week ending 07 November 1997

The following Out-of-Limit (ALARM) conditions were detected:

MNEMONIC      STATE         DESCRIPTION                      ORBITS
---------     -----         ------------                     ------
OBSVLBEON     R-LO     Load Bus Volts at EON        Continuous
OBSBATVEON2   R-LO     Battery 2 voltage at EON     Continuous
OBSBATVEON3   R-LO     Battery 3 voltage at EON     Continuous
OBSVLBEON     Y-LO     Load Bus Volts at EON        33616-23
OBSBATVEON2   Y-LO     Battery 2 voltage at EON     33616-23
OBSBATVEON3   Y-LO     Battery 3 voltage at EON     33616-23
OBSSOC2       Y-LO     Battery 2 Current SOC        33557,63,78,86,92,
                                                    33606,8,17,23,32,8,45,8
MLSCANACTTMP  R-LO     Scan Actuator temp.          33608,9
WIEUTEMP      Y-LO     WINDII EU Temperature        33638-53
SOSTMPRNTRN   Y-LO     Temperature Entrance         33647,8
ACTEMPANA2    Y-LO     Temp ACR 2                   33647,8
NBRECBI       Y-HI     NBTR B RECORD CURRENT        33648
PWLBV         R-LO     CURRENT LBV                  33648
PWBAT2V       R-LO     BATT. 2 CURRENT VOLTAGE      33648
PWBAT3V       R-LO     BATT. 3 CURRENT VOLTAGE      33648


The following ALERT occurrences were detected:

MNEMONIC                   DESCRIPTION                     ORBITS
---------                  ------------                    ------
OBSZ1OOL     UFLTR Z1 Residual Exceeded 100 Arcsec  33646



                                APPENDIX C
                 CLOCK & SOLAR ARRAY RATE CORRECTIONS
                       Week ending 07 November 1997

                      CLOCK DRIFT RATE ADJUSTMENTS

     ORBIT              TIME                 CLOCK RATE CHANGE
     -----              ----                 -----------------
     33617     309/14:13 (05 Nov 97)     from 00.0 to 20.6 msec/day
     33634     310/17:37 (06 Nov 97)     from 20.6 to 00.0 msec/day


_______________________________________________________________

                             APPENDIX D
                    UARS BATTERY PERFORMANCE DATA
                       Week ending 07 November 1997

     01 Nov. 1997 - GMT Day 305 Beta = 22.7 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   -2.42/-3.51   +0.0/ +0.0   18.7     0.000    0.0
2    +78.4/  +0.0   +7.74/+6.44  +31.0/-16.0   24.2     1.022   24.1
3    +67.2/  -5.6   +6.44/+5.15  +30.0/-15.4   24.2     1.023   23.3

     07 Nov. 1997 - GMT Day 311 Beta =  3.0 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   -3.05/-3.99   +0.0/ +0.0   18.7     0.000    0.0
2    +44.8/ -22.4   +7.28/+5.79  +30.5/-15.9   23.4     1.019   23.9
3    +50.4/ -11.2   +5.79/+4.51  +29.5/-15.4   23.2     1.020   23.0


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

_______________________________________________________________
                                    APPENDIX E
                              UARS ANOMALY REPORTS
                            Week ending 07 November 1997

AR NO.   SUBSYS       ORBIT      TIME       TTR      PROBLEM/DATA LOSS
------   ------       -----      ----       ---      -----------------
97-119     FOT        33569    306/0809    14170     Generic Late Acquisition
97-120     FOT        33570    306/0952     N/A      RTS 001 tripped


              ANOMALY CLOSURE INFORMATION RECEIVED
AR NO.   SUBSYS       ORBIT      TIME       TTR      PROBLEM/DATA LOSS
------   ------       -----      ----       ---      -----------------
97-111     FOT        FIVE                 14170     OCT GENERIC LATE ACQ
97-118     FOT        33518    302/23:22   19566     NEG ACQ
97-120     FOT        33570    306/09:52             TMON 01 TRIP-LO VOLT


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