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UARS WEEKLY STATUS REPORT - 05 NOV 1999
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SOLSTICE
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SOLSTICE continues to operate normally, collecting solar data on all
available orbital tracking periods and stellar calibration observations,
whenever possible.
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SUSIM
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SUSIM was affected by telemetry outages caused by the temporary loss of
the UARS onboard tape recorder. Incomplete daily scans were obtained on
October 31 and November 1. Afterwards, SUSIM successfully gathered its
normal solar and occultation data without apparent problems. Originally
scheduled offset scans will be rescheduled if the telemetry remain stable.
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ACRIM
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Nothing received.
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PEM
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Geoff Crowley represented PEM at the UARS science team meeting in
Virginia Beach, October 26-28. Dr. Crowley presented the PEM status, a paper
titled "Simulation of the Solstice Mesopause" (G. Crowley, G. Thomas R. Roble,
J. Olivero, and H. Liu), and a poster titled "Climatology for Studying the
Effects of Particles on the Atmosphere" (R. Frahm, J. R. Sharber,
J. D. Winningham, G. Crowley, A. J. Ridley and R. Link).
The PEM spectrometers continue to be active under PMON control. While
under PMON control, the PEM instrument computed energy deposition from
electrons and protons measured in-situ by the particle spectrometers.
The FOT and the PEM team are have completed updating the PEM activation
sequence which effects the PEM/HEPS (> 30 keV particles). PEM PMON
activation is set for the beginning of power orbit day. The beginning of
power orbit day is defined as when: array current >5 amps, and array
voltage >53.5 volts, and battery current >2.0 amps. The end of power orbit
day (PEM deactivation) is defined as when: time in power orbit day >4 minutes,
and array current <9 amps, and battery currents <0.2 amps. Power orbit day
periods vary depending upon beta angle: about 39-40 minutes at yaw to
about 50-51 minutes at max beta. Thanks to Dimitrios Mantziaras of the FOT
for assisting PEM with the activation sequence timing.
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HALOE
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HALOE was powered on beginning-of-day today November 5, 1999. All
engineering parameters are within their nominal operating region.
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MLS
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Nothing received.
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HRDI
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Nothing received.
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WINDII
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WINDII is standing by, following the delay of the activation
originally schedule for Nov. 3. A WINDII Science Team meeting
is planned to take place in Toronto, Nov. 24/25, 1999.
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MPG
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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
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The CDHF notified PI Software Representatives regarding data gaps
for UARS DAYS 2967, 2968, 2971, 2972, and 2973 that occurred as a result
of the UARS Tape Recorder Anomaly.
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.
1 day ATT (7.3) PROD (1R-1C=0L)
18 days CLA (7.0) PROD (L1-L3) (476R-355C-17F=104L)
34 days GPI (4.05) PROD (CLAES L3B) (278R-260C-1F=17L)
1 day OBC (3.4) PROD (1R-1C=0L)
1 day SEN (5.0) PROD (1R-1C=0L)
2 days SEN (5.0) PROD (1992) (2R-2C=0L)
The CDHF has completed testing WINDII V5.11A formal software delivery.
CDHF REHOST:
The CDHF received a "PASS" status on all 4 jobs testing HALOE V4.82
on the Rehost System. Report and log files are being reviewed.
We are moving output files resulting from recent HALOE 4.82 tests to a
central area on the current production system for HALOE's inspection.
CDHF pending software upgrades: none
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FOT
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REPORTING PERIOD
This report covers 23 October, 1999 (Orbit 44346, GMT Day 296) through 29
October 1999 (Orbit 44450, GMT Day 302).
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 296/2214 44359 Off
HALOE 299/2300 44405 Off
The beta angle ranged between the angles of 27.0 degrees to 0.8 degrees for
this report period. The beta angle is now increasing toward a maximum angle of
76 degrees on 18 November 1999 (DOY 322).
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 23.7 V end-of-night (EON) load bus voltage. Battery
temperatures are stable with a temperature delta between Battery 2 and Battery
3 of 1.0 to 1.3 degrees C. Additional battery performance data for each
battery on 22 October 1999 and 29 October 1999 are provided in Appendix D.
The clock error ranged from -9.3 to -6.1 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 = 01
The following real-time command sheets were executed for the listed operational
element(s) during this report period (see Appendix A).
% HALOE = 01
% WINDII = 01
% FOT = 01
UARS Anomaly Reports initiated during this report period are listed in Appendix
E and summarized below.
% FOT = 03
Two (2) Anomaly Reports remained OPEN at the end of this report period (see
Appendix E).
TRANSPONDER FREQUENCIES:
% Transponder A: 99/263 - 2287.496947
% Transponder B: 99/265 - 2287.498700
GROUND SYSTEM OPERATION
Three (3) 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 99/301 show the observatory data loss to be 31 hours, 44
minutes, 08.609 seconds (an increase of 0.384 seconds since the last report
period). This is a 0.0448 percent data loss which equals a 99.9552 percent
data capture for the mission.
The increase of 6 hours 48 minutes 13.773 seconds occurred over three (4) days:
7 4.301 seconds on Day 298 due to a Forward Link failure.
7 3 hours 11 minutes 28.224 seconds on Day 299. Data not recoverable and under
investigation.
7 3 hours 36 minutes 40.736 seconds on Day 300. Data not recoverable and under
investigation.
7 0.512 seconds on Day 301 due to data hit.
OTHER SIGNIFICANT EVENTS
UARS SATELLITE OPERATIONS
A Forward-to-Reverse Yaw Around maneuver (number 83) was successfully executed
in Orbit 44430 beginning 301/15:13:52 and completing at 301/15:51:02 on 28
October 1999. The SSPP Instruments (ACRIM, SOLSTICE, SUSIM) were enabled as
well as HRDI and PEM in day only operations. Due to the SA position at 269
degrees, the effective night length of the spacecraft after the maneuver was
approximately 50 minutes. Post maneuver analysis of data indicate that during
the Yaw Around, the end-of-night load bus voltage was 23.8 volts and the
average depths of discharge (DODs) on Batteries 2 and 3 were approximately 23.5
and 24.0 percent respectively. The next (reverse-to-forward) YAW is scheduled
for 08 December 1999 (DOY 301).
On Wendesday October 26, DOY 299 NBTR B playback data capture problems occured.
The FOT investigated the problem by reviewing data from White Sands, UARS
Telemetry Processing Facility (TPF) and spacecraft telemetry. The failed
playbacks were non repetitive and eventually cleared by the end DOY 300.
Preliminary investigation did not reveal any anomalous conditions with NBTR B,
its accompying hardware or the Pre-Modulation Processor. The FOT did concur
with the observations of White Sands Communication Services Controllers that
errant bit synch existed with the failed playbacks. NBTR B operation remained
unchanged going into the weekend. This problem reoccurred during the weekend
on October 30 and 31. NBTR B operations were suspended until further notice.
Next weeks report will include specifics from the anomaly investigation.
YEAR 2000 OPERABILITY SUPPORT
A Y2k DFLX test was accomplished on Thursday, 28 October. This test consisted
of transfering ATC files from the CMS to DFLX. DFLX prepares the loads to the
NASCOM recognized 4800 bit format prior to copying to the AP and then out to
the spacecraft. These files were then run through a simulated uplink with 100
percent success.
MEETINGS
Flight Operations Team representatives attended the Science Team Conference in
Virginia Beach on October 26 - 28. The FOT gave an overview on the status of
the spacecraft to help kick off the start of the conference. The next two days
involved presentations on each of the Science Teams investigations. On
Wendesday at the end of the conference, a detailed discussion of the Deboost
proposal was held. The FOT fielded questions regarding the health of the
spacecraft, its predicted end of life and operating costs for the mission. The
main concern that the principal investigators expressed was that the mission
should be continued as long as meaningful data could be collected. A Deboost
proposal could be discussed but should not inhibit the mission if it is healthy
enough to last beyond 2003 when new budgeting would have to be allocated.
FUTURE SIGNIFICANT EVENTS
A second meeting to discuss the UARS Safehold configuration and concerns for
the MPS and its batteries is planned for Friday, November 5th. This meeting
will be a closed meeting with only the FOT and specialized engineering support
attending.
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 29 October 1999
ORBIT AOS NO. SUBSYS REASON
----- --- --- ------ -------
44359 296/2214 99-348 WINDII Power OFF
44405 299/2300 99-349 HALOE Power OFF
44429 301/1342 99-350 OBC Yaw Around - REV Flight
__________________________________________________________________
APPENDIX B
OUT-OF-LIMITS & ALERTS OCCURRENCES
Week ending 29 October 1999
The following Out-Of-Limits occurrences were detected:
MNEMONIC STATE DESCRIPTION ORBITS
--------- ----- ------------ ------
HRPTSPBIMON R-LO HRDI Pulse Bus Current Monitor 44419
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 29 October 1999
CLOCK DRIFT RATE ADJUSTMENTS
ORBIT TIME CLOCK RATE CHANGE
----- ---- -----------------
None this report period
APPENDIX D
UARS BATTERY PERFORMANCE DATA
Week ending 29 October 1999
22 Oct 1999 - GMT Day 295 Beta = 27.0 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/-3.99 +0.0/+0.0 16.3 0.000 0.0
2 +16.8/-44.8 +6.11/+5.15 +32.0/-15.2 24.6 1.022 21.9
3 +16.8/-106.4 +5.15/+3.87 +31.2/-16.0 24.5 1.022 21.7
29 Oct 1999 - GMT Day 288 Beta = 0.8 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 -89.6/-112.0 -3.05/-4.31 +0.0/+0.0 16.3 0.000 0.0
2 +56.0/-5.6 +6.44/+5.15 +30.4/-14.0 23.8 1.017 22.2
3 +22.4/-100.8 +5.15/+3.87 +29.6/-14.4 23.8 1.018 21.8
V/T LEVEL CHANGES
ORB# TIME LVL FR-TO
----- ---------- ----------
no changes V/T 5
APPENDIX E
UARS ANOMALY REPORTS
Week ending 29 October 1999
NEW ANOMALY REPORTS GENERATED
AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
99-070 FOT 44387 298/1919 21509 Forward Link Failover
99-071 FOT 44398 299/1212 21512 TPF Not Receiving 512 PB
99-072 FOT 44429 301/1342 N/A TAC 8 Crashed
ANOMALY CLOSURE INFORMATION RECEIVED
AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
99-070 FOT 44387 298/1919 21509 Forward Link Failover
99-072 FOT 44429 301/1342 N/A TAC 8 Crashed
ANOMALY INVESTIGATION REPORTS GENERATED
AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
99-071 FOT 44398 299/1212 21512 TPF Not Receiving 512 PB
OPEN ANOMALY REPORTS
AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
99-064 FOT 44135 10/8-9/99 N/A HRDI Cal Lamp Errors
99-071 FOT 44398 299/1212 21512 TPF Not Receiving 512 PB
SEVNTFW99/44