UARS Weekly Status Report

11 September 1998





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                UARS WEEKLY STATUS REPORT - 11 Sep 1998

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

SOLSTICE is currently in daylight only operations. During this limited 
operation we are successfully gathering a full solar data set each day 
however no stellar calibration measurements are made. Normal operations 
will resume on Tuesday (98258).

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

SUSIM was turned off on Monday, Sept. 7.  We expect to be turned back
on Monday, Sept. 14.  While on, SUSIM successfully gathered its normal
solar, offset, and occulation data during this past week without
apparent problems.

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

     PEM was not active

     GSFC has proposed an OBC operation plan for the activation of PEM boom 
instruments during the daylight portions of every orbit.  This OBC operation 
plan is accepted by PEM.  PEM has proposed a series of test procedures for 
activation and is waiting response from GSFC.  PEM is also waiting for GSFC
scheduling and implementation of the OBC plan and its operation test procedures.

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

HALOE continues successful operations with all engineering parameters being
nominal.  Science data products continue to be excellent.

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

Nothing received.

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

Nothing received.

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

Nothing received.

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

Routine processing of instrument Daily Activity Plans continues 
with no other 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.
           
             76 days HAL (4.80) PROD (L1)    (1873R-1389C-25F=459L)
             62 days HAL (4.80) PROD (L3)    (1873R-776C=1097L)
            105 days SOL (4.62) PROD (L2-L3) (2349R-1440C=909L)
              6 days SUS (7.00) ENG          (41R-41C=0L)

The CDHF has upgraded the FORTRAN compiler from v6.3 to v6.5 on CDHF2 and
CDHF5.
  
CDHF pending software upgrades: IDL 5.1, OpenIngres.
                  
***********
FOT
***********

REPORTING PERIOD

This report covers 29 August 1998 (Orbit 38056, GMT Day 241) through 04 
September 1998 (Orbit 38160, GMT Day 247).


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
     HALOE        240/0037     38041     On
     HRDI         242/0038     38071     On

A summary of Instrument operations supplied by the Mission Planning Group 
for the month of August 1998 is contained in Appendix F, UARS Instrument 
Operations Summary.

The beta angle ranged between the angles of 13.0 degrees to 39.0 degrees 
for this report period.  The beta angle is now decreasing toward a minimum 
angle of 52.0 degrees on 11 September 1998 (DOY 254).

A series of SSPP gridded offset maneuvers requested by SUSIM operations 
were performed on GMT days 241-246.  This offsets utilized the 5 and 10 
arcminute intervals, versus the 15 and 30 arcminute intervals.

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 0.9 to 1.3 degrees C.  Additional battery performance data 
for each battery on 28 August 1998 and 04 September 1998 are provided in 
Appendix D.

The clock error ranged from 11.2 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        =     00
%     OUT-OF-LIMITS =     10

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

%     FOT     03
%     HRDI    04
%     HALOE   02

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

%     FOT     05

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

TRANSPONDER FREQUENCIES:
     Transponder A:  98/210  -  2287.496941
     Transponder B:  98/211  -  2287.499161


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 98/246 show the observatory data loss to be 
21 hours, 05 minutes, 01.524 seconds (an increase of 15.424 seconds since 
last report period).  This is a 0.0346 percent data loss which equals a 
99.9654 percent data capture for the mission.

The increase of 15.424 seconds occurred on Day 240 and was due to a hit in 
data plus insufficient overlap.

Testing of the operational pack version of Application Processor (AP) 
software version 10.12 continued.  The test goals for acceptance were 
completed on 31 August and 01 September 1998 using the UARS simulator 
(UTTS).  Verbal approval was given to MSOCC to build operational packs.  
First operational use of version 10.12 was on 04 September 1998 supporting 
the 1524Z contact.  Operations were nominal except that the Clock Delta 
equation processor did not function.  Troubleshooting led to a theory that 
the database and software were incompatible.  Plans to correct the database 
next week are in place

The FOT made modifications to the OBCSTF resident POCC database on 04 
September 1998.  The purpose of the database modifications was to add two 
additional Equation Processor records to allow for correct clock delta 
calculations.   The clock delta calculations were previously performed 
using an FOT supplied constant value via the LIMDEF STOL procedure.  Due to 
a recent AP software update, the clock delta calculations are now being 
performed differently, hence the need for the two additional database 
records.  The database (version 68) will be tested next week.


OTHER SIGNIFICANT EVENTS

UARS SATELLITE OPERATIONS

FOT continues to improve a power profile for UARS based on the current 
status of the Modular Power System.

YEAR 2000 OPERABILITY SUPPORT

UARS Test and Training Simulator (UTTS) No change to report.

User Planning System (UPS) - No change to report.

Multi Satellite Operations Control Center (MSOCC) - No change to report.

Command Management System (CMS) - The FOT attended the weekly CMS Year 2K 
Testing status on 03 September.  Topic of discussion was the general status 
of the testing.

The FOT worked with CMS Year 2K Test Team Sidney Kirschner this week in a 
continuing effort to make progress on the Year 2K test functions.  Several 
more FDF test files were received by the FOT this week, all of which were 
processed on the back-up CMS system.  The FOT and Mr. Kirschner were able 
to successfully process the Star Interference file as well as the TDRS East 
and TDRS West ephemeris files.  Errors were received when processing the 
UARS OBC ephemeris file because the file not containing enough data.  In 
addition, the Spacecraft Orbital Events file could not be processed because 
there was no corresponding PSAT file, which is required by the CMS.  
Finally, the CMS could not successfully process the predicted Spacecraft 
Ephemeris file due to the apparent inability of the CMS to interpret the 
rollover from year 1999 to 2000.  Further testing is planned for next week.

Flight Dynamics Facility (FDF) - Year 2K planning aids have been generated.

OBC PMON FLIGHT SOFTWARE UPDATE

Flight Software - Complete.

Ground Support Software - Complete.

Verification Testing - Testing of the operational version of the pack 
complete.  On-line testing revealed a problem with the delta time 
calculation.  Problem under investigation.

IP NETWORK TESTING

Space Network (SN) - 512kbps tape recorder playback to TPF using the IP 
data stream was successful on 31 August 1998 (Orbit 38127 245/1848 UTC).  
TPF locked on the tape recorder dump when commanded by the FOT and the 
playback appeared free of errors on the TPF data quality display.  Nominal 
errors at the end of the playback were noted which are also received during 
a nominal NASCOM playback.  The TPF analyst reported that the post event 
processing was good.  Test of the 32kbps non coherent high antenna using 
the IP link was also successful.  Realtime data was received with no poly 
errors and commanding was nominal. 32kbps Bank dumps were commanded and 
banks 0-15 were downlinked successfully.  A test of the 1kbps data link 
from the UARS OMNI antenna using the IP link was successfully performed in 
Orbit 38139 (246/1443 UTC).

Testing with the NCC 98 system to support routine flight operations is 
being planned.

Deep Space Network (DSN) and Ground Spaceflight Tracking and Data Network 
(GSTDN) - Working with the DSN test lead for I/P testing to verify UARS 
emergency backup sites.

UARS PROPULSION MODULE B/D THRUSTER LINE FILL

The B/D thruster refill effort continues.  The Eaton Latch Valve test 
report has been received.  A copy of the report was provided to the UARS 
FOT by Dennis Asata, GSFC Propulsion Branch, on 02 September 1998 for 
review and comment.

UARS RE-ENGINEERING - TELEMETRY PROCESSING

Flight operations is providing support to the re-engineering effort to 
process the UARS telemetry on the TOMS/EP control center computer system.

UARS COMMAND RE-HOST PHASE 1 DEMONSTRATION

Flight operations continues to support the update of the Lockheed Martin 
SCS-21 control center system to support a phase 1 feasibility demonstration

SCS-21 testing continued this week.  Testing with the SOC computer system 
that emulates the NCC system was conducted.  This test was not successful 
in that error messages could not be translated and received blocks could 
not be dumped at the SOC.  However, FOT continued to test the command 
portion of the SCS-21 software.  Single ground commands continue to work 
between the UTTS and SCS-21.  Spacecraft loads were sent from SCS-21 to 
UTTS and were blocked and received properly.  However, there was a problem 
with the transmission of the UARS Spacecraft ephemeris load.  The 
transmission of this load caused the UTTS OBC to crash on several attempts.  
A bad load was suspected; therefore, another spacecraft ephemeris was 
transferred, converted and loaded in the UTTS without problem.  The bad 
load was attributed to a problem with file transfer using FTP which 
currently has no CRC check on transmission/receipt.

Testing with NCC 98 system was conducted on 01 and 03 September 1998. NCC 
98 reported several problems with the GCMRUs such as missing message type, 
ID, and class areas in the data portion of the block.  These were corrected 
and NCC 98 accepted our GCMRUs and gave good responses back to SCS-21.  
SCS-21 received good disposition and acknowledgments from NCC 98.  Good ODM 
data was also received.


MEETINGS

FOT supported a UARS Battery telecon on 25 August 1998.   The next telecon 
has been scheduled for 22 September 1998 at 1:00 pm.


FUTURE SIGNIFICANT EVENTS

The next UARS Yaw Around Maneuver is scheduled for scheduled for 29 
September 1998.

The United States Naval Observatory (USNO) issued  a Time Service 
announcement advising that  the International Earth Rotation Service (IERS) 
will retard UTC time by 1.0 second at the end of December 1998. This means 
the addition of one leap second as the last second of 1998.

The next annular solar eclipse will occur on 16 February 1999 over the 
Indian Ocean, Australia and the South Pacific Ocean.


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 F,  UARS Instrument Operations Summary



                               APPENDIX A
                       REAL-TIME COMMAND SHEETS
                      Week ending 04 September 1998

ORBIT      AOS      NO.     SUBSYS        REASON
-----      ---      ---     ------        -------  
38041   240/0037   98-313   HALOE   Power ON (with PB off)
38045   240/0820   98-315   HALOE   Pulse Bus on
38052   240/1937   98-316   HRDI    Htr Cycle to 100 amp min
38071   242/0038   98-317   HRDI    Power ON
38072   242/0223   98-318   HRDI    Survival HTR On
38073   242/0453   98-319   HRDI    Power ON 
38074   242/0626   98-320   OBC     Clk Adj fr 0.00 to 20.6 msec/day
38092   243/1144   98-321   OBC     Clk Adj fr 20.6 to 0.00 
38136   246/1021   98-323   OBC     Clk Adj fr 0.00 to 20.6 



_______________________________________________________________

                               APPENDIX B
                  OUT-OF-LIMITS & ALERTS OCCURRENCES
                      Week ending 04 September 1998

MNEMONIC      STATE      DESCRIPTION                      ORBITS
---------     -----      ------------                     ------
WIEUTEMP     Y-LO     WINDII EU Temperature       38056-38160
HAH28VA      R-LO     HALO28V HTRMTR              38041-45
QTSISAIF     Y-HI     SSPP Baseplate by SISA I/F  38052-4,68
OBSVLBEON    Y-LO     Load Bus Volts at EON       38072
OBSBATVEON2  Y-LO     Battery 2 voltage at EON    38072
OBSBATVEON3  Y-LO     Battery 3 voltage at EON    38072
HRPSEQBIMON  Y-HI     HRDI Pulse Bus Cur. Mon     38074
HRPTSPBIMON  Y-HI     HRDI PTS Pulse Bus I Mon    38103
SOSNTGRSBTM  R-HI     SOLSTICE Integration        38107
HRIFESURVTMP Y-HI     HRDI IFE Survival Htr Temp  38073     



The following ALERT occurrences were detected:

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



_______________________________________________________________

                               APPENDIX C
                 CLOCK & SOLAR ARRAY RATE CORRECTIONS
                      Week ending 04 September 1998


                      CLOCK DRIFT RATE ADJUSTMENTS

     ORBIT              TIME                 CLOCK RATE CHANGE
     -----              ----                 -----------------
     38074     242/06:46 (30 Aug 98)     from 00.0 to 20.6 msec/day
     38092     243/11:50 (31 Aug 98)     from 20.6 to 00.0 msec/day
     38136     246/10:30 (03 Sep 98)     from 00.0 to 20.6 msec/day


_______________________________________________________________

                               APPENDIX D
                    UARS BATTERY PERFORMANCE DATA
                      Week ending 04 September 1998


     28 Aug 1998 - GMT Day 240 Beta = 13.0 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  -2.73/-4.31  +0.0/ +0.0    18.1     0.000   0.0
2   +89.6/ 0.0    +7.09/+4.51 +31.2/-15.2    24.2     1.020  23.1
3   +78.4/ 0.0    +5.79/+3.55 +30.4/-16.0    24.2     1.020  22.6


     04 Sep 1998 - GMT Day 247 Beta = 39.0 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  -2.42/-3.68  +0.0/ +0.0    18.1    0.000     0.0
2   +39.2/-5.6    +6.44/+5.15 +28.8/-16.0    25.1    1.023    22.3
3   +44.8/-11.2   +5.47/+3.87 +28.4/-16.0    25.1    1.026    21.7


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



                               APPENDIX E
                         UARS ANOMALY REPORTS
                      Week ending 04 September 1998


                       NEW ANOMALY REPORTS GENERATED
  AR NO.   SUBSYS   ORBIT   TIME       TTR      PROBLEM/DATA LOSS
  ------   ------   -----   ----       ---      -----------------
98-054   FOT      38045  240/0820   N/A     AP Crashed,ODN down
98-056   FOT      38111  244/1808   N/A     3 errs on S/C ephem dump
98-057   FOT      38151  247/0945   14170   Generic Late Acquisition
98-057   FOT     38155   247/1646   14170   Generic Late Acquisition
98-058   FOT     N/A     247/2100   N/A     CMS Load Transfer Problem


                   ANOMALY CLOSURE INFORMATION RECEIVED
  AR NO.   SUBSYS   ORBIT   TIME      TTR      PROBLEM/DATA LOSS
  ------   ------   -----   ----      ---      -----------------
98-045     FOT     AUG 98  SEE LIST  14170    GENERIC LATE ACQ.
98-052     FOT             DAY 234            GRD LOAD TRANSFER
98-055     FOT     38072   242/02:23          TMON 1 TRIP
98-056     FOT     38111   244/18:08          GRD MASK ERRORS


                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
  ------   ------   -----  ----       ---      -----------------
98-057    FOT    SEPT 98 SEE LIST   14170    GENERIC LATE ACQ



_______________________________________________________________
                               APPENDIX F
                   UARS INSTRUMENT OPERATIONS SUMMARY
                      Week ending 04 September 1998


              INSTRUMENT SUMMARY FOR MONTH OF August 1998 (hours)


                                    UNPLANNED      UNSCHEDULED
                 ON        OFF         OFF             OFF     
                                   (Insufficient   (Other than
Instrument    (Actual) (Scheduled)       Power)   Power Problem)  COMMENTS
----------     ------  ----------- -----------   ------------- ------------

ACRIM           744      0              0              0

HALOE           300      434            10             0

HRDI            185      554            5              0

MLS             286      458            0              0

PEM (axis)      165      579            0              0

PEM (zeps)      22       722            0              0

PEM (neps)      0        744            0              0

SOLSTICE        744      0              0              0

SUSIM           744      0              0              0

WINDII          235      509            0              0



Cold side of spacecraft was facing northward:   06.5 days
Cold side of spacecraft was facing southward:   24.5 days