********************************************************************
UARS WEEKLY STATUS REPORT - 16 APR 1999
********************************************************************
***********
SOLSTICE
***********
SOLSTICE continues to operate normally, collecting solar data on all
available orbital tracking periods and stellar calibration observations,
whenever possible.
***********
SUSIM
***********
After turning back on April 11th, SUSIM gathered its normal solar,
offset, and occultation data without apparent problems.
Reprocessing of the SUSIM data to version 20 continues.
***********
PEM
***********
PEM is active under PMON control. Energy processor #6 for the HEPS-1 unit
is activating correctly now. The PEM team and FOT found that the entanglement
of energy processor #6 was related to the differences between OBC activation
commanding and activation commanding from the ground. Attempts at adjusting
OBC command timing failed until the correct combination of command sequence was
found. The FOT and the PEM team are completing close-out documentation on this
problem.
While under PMON control, the PEM instrument computes energy deposition
from the particle spectrometers.
***********
HALOE
***********
HALOE continues successful operations with all engineering parameters with
nominal operating range. Science data products are of excellent quality.
***********
MLS
***********
MLS was reactivated successfully on Apr 4 and performed north viewing
operations through Apr 10. The instrument is now off as scheduled. MLS is
scheduled to begin south viewing operations on May 11 and operate through
May 28.
***********
HRDI
***********
Nothing received.
***********
WINDII
***********
Nothing received.
***********
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.
50 days PEM (3.32) PROD (OA-L2) (760R-478C-1F=281L)
392 days WIN (5.11) PROD (LOG) (2014R-1061C=953L)
43 days WIN (5.11) PROD (L1-L3) (2014R-192C=1822L)
CDHF pending software upgrades: DEC AXP Fortran 6.5, DEC AXP OPEN
VMS 6.2, OpenIngres.
SOLSTICE Wallclock "The second attempt to run SOLSTICE debug step 2 as a
test production job on the operational system Alpha was unsuccessful.
It terminated in a "general unrecoverable error". This run had incorporated
more specific debug indicated by previous run (as well as a modification to
the link procedure to ensure that debug software was getting included).
Investigation of this problem will take place next week."
***********
FOT
***********
REPORTING PERIOD
This report covers 03 April 1999 (Orbit 41305, GMT Day 093 through 10 April
1999 (Orbit 41424, GMT Day 100).
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 094/0029 41320 AXIS Off
MLS 094/0029 41320 On
PEM 098/0032 41380 AXIS-1 On
MLS 100/2314 41424 Off
The beta angle ranged between the angles of 19.8 degrees to 41.4 degrees
for this report period. The beta angle is now increasing toward a maximum
angle of 77 degrees on 21 May 1999 (DOY 141).
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 1.0 to 1.3 degrees C. Additional battery performance data
for each battery on 02 April 1999 and 09 April 1999 are provided in
Appendix D.
The clock error ranged from 11.2 to -10.7 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 = 04
The following real-time command sheets were executed for the listed
operational element(s) during this report period (see Appendix A).
% FOT 04
% MLS 05
% PEM 02
UARS Anomaly Reports initiated during this report period are listed in
Appendix E and summarized below.
% FOT 04
Three (3) Anomaly Report remained OPEN at the end of this report period
(see Appendix E).
TRANSPONDER FREQUENCIES:
Transponder A: 99/054 - 2287.496923
Transponder B: 99/055 - 2287.498750
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 99/098 show the observatory data loss to be
22 hours, 47 minutes, 05.684 seconds (an increase of 28.288 seconds since
last report period). This is a 0.0345 percent data loss which equals a
99.9655 percent data capture for the mission.
The increase of 28.288 seconds occurred over three (3) days:
7 9.536 seconds on Day 095 due to WSGT being unaware of support; not
received on next tape dump,
7 0.960 seconds on Day 096 due to data hit, and
7 17.792 seconds on Day 097 due to IP hits.
FOT received a valid "test" Y2K Spacecraft Orbital Events file from FDF
this week. The file was processed on the CMS and made available to the MPG
for distribution to any interested instrument operations teams. The FOT is
still awaiting the delivery of one other test Y2K file, the 8-week Ground
Track file. This file is expected to be delivered by FDF next week.
The FOT re-built two versions of RTS 12 on 9 April. The purpose of the RTS
versions is to temporarily alter the heater duty cycle to allow the SUSIM
instrument to be "warmed up" during the 12 hour period prior to their
scheduled power-on process on 11 April. To facilitate this "warming up",
the FOT will load a new version of RTS to cycle both the A and B sides of
compensation heater 18. Currently, RTS 12 only turns on the A side of this
heater. The normal version of RTS 12 will be re-loaded after the SUSIM
power-on process is completed.
OTHER SIGNIFICANT EVENTS
UARS SATELLITE OPERATIONS
The FOT continues to support the PEM team with diagnosis of the Energy
Processor 6 status error.
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 - No change
UARS PROPULSION MODULE B/D THRUSTER LINE FILL
Planning continues for the simulator testing.
MEETINGS
FOT supported an IMOC meeting on 07 April 1999.
UARS supported the first Monthly Project Meeting held on 07 April 1999.
Representatives from Central Data Handling Facility (CDHF), Flight Dynamics
Facility (FDF), Flight Operations Team (FOT), Y2K testing, CSOC customer
services and NASA GSFC (Project Scientist and Mission Director) were
present.
FUTURE SIGNIFICANT EVENTS
The next UARS Yaw Around Maneuver (reverse-to-forward) is scheduled for 30
April 1999 (DOY 120).
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 April 1999
ORBIT AOS NO. SUBSYS REASON
----- --- --- ------ -------
41320 094/0029 99-121 PEM AXIS Power OFF
41320 094/0029 99-124 MLS Power ON
41337 095/0345 99-125 MLS MLS Microload
41359 096/1555 99-125 OBC Clk Adj fr 0.00 to 20.6 msec/day
41380 098/0032 99-126 PEM AXIS-1 ON Only
41385 098/0926 99-127 OBC Clk Adj 20.6 to 0.00 msec/day
41387 098/1238 99-128 MLS Scanner Off - Temp High
41396 099/0217 99-129 MLS Scan Actuator on
41417 100/1204 99-130 OBC Clk Adj fr 0.00 to 20.6 msec/day
41421 100/1732 99-131 PMON Enabled Comp Htr 18 A&B sides
41424 100/2314 99-132 MLS Power OFF
_______________________________________________________________
APPENDIX B
OUT-OF-LIMITS & ALERTS OCCURRENCES
Week ending 09 April 1999
MNEMONIC STATE DESCRIPTION ORBITS
--------- ----- ------------ ------
QTSSPPMX Y-HI SSPP -X Thermostat 41386,90-92
MLSCANACTTMP R-LO MLS Scanner Temp 41387
PEAXTHERM6E Y-HI AXIS Temp Monitor #6 41389-92, 403-09
QTSSPPMX Y-HI SSPP -X Thermostat 41405
The following ALERT occurrences were detected:
MNEMONIC DESCRIPTION ORBITS
--------- ------------ ------
None this report period
_______________________________________________________________
APPENDIX C
CLOCK & SOLAR ARRAY RATE CORRECTIONS
Week ending 09 April 1999
CLOCK DRIFT RATE ADJUSTMENTS
ORBIT TIME CLOCK RATE CHANGE
----- ---- -----------------
41359 096/15:58 (06 Apr 99) from 00.0 to 20.6 msec/day
41385 098/09:30 (08 Apr 99) from 20.6 to 00.0 msec/day
41417 100/12:11 (10 Apr 99) from 00.0 to 20.6 msec/day
_______________________________________________________________
APPENDIX D
UARS BATTERY PERFORMANCE DATA
Week ending 09 April 1999
02 Apr 1999 - GMT Day 092 Beta = 19.8 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 -33.6/-56.0 -3.05/-4.31 +0.0/ +0.0 16.6 0.000 0.0
2 +89.6/ 0.0 +6.11/+5.15 +30.8/-15.2 24.8 1.024 21.4
3 +56.0/-5.6 +5.15/+3.87 +30.4/-16.0 24.5 1.023 21.5
09 Apr 1999 - GMT Day 099 Beta = 41.4 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 -44.8/-67.2 -3.05/-4.31 +0.0/ +0.0 16.6 0.000 0.0
2 +100.8/0.0 +6.11/+5.15 +28.8/-15.2 24.5 1.022 21.9
3 +22.4/-50.4 +5.15/+3.87 +28.4/-16.0 24.5 1.025 21.8
V/T LEVEL CHANGES
ORB# TIME LVL FR-TO
----- -------- ----------
no changes V/T 5
APPENDIX E
UARS ANOMALY REPORTS
Week ending 09 April 1999
NEW ANOMALY REPORTS GENERATED
AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
99-015 FOT 41336 095/0128 20739 Neg Acq-Pass not on sked.
All data recovered.
99-017 FOT 41378 097/2115 14170 Generic Late Acquisition
99-017 FOT 41384 098/0744 14170 Generic Late Acquisition
99-017 FOT 41421 100/1732 N/A File Transfer PENDING
ANOMALY CLOSURE INFORMATION RECEIVED
AR NO. SUBSYS ORBIT TIME TTR PROBLEM/DATA LOSS
------ ------ ----- ---- --- -----------------
99-011 FOT see list Mar 99 14170 Generic Late Acq
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
------ ------ ----- ---- --- -----------------
99-017 FOT see list Apr 99 14170 Generic Late Acq
99-014 FOT 41189 085/0548 N/A CRC Errors in PBK
99-015 FOT 41336 095/0128 20739 Neg Acq-Pass not on sked.
All data recovered.
SEVNTFW99/15