ACE Weekly Report 01-30-02

All ACE spacecraft subsystems are performing nominally.  Attitude
maneuvers were successfully performed on 01/14/02 and 01/25/02.  The
next attitude maneuver is scheduled for 02/05/02.

OCR SIS-027 was executed on 01/24/02 to disable and raise firmware
thresholds on matrix detection strips.  One result differed from what
was expected.

OCR SIS-025 was executed on 01/25/02 to restore the M1B values to their
pre-OCR SIS-027 values.  The M1A detector values from SIS-027 did work
as expected.  The instrumenter continues his investigation of the
anomalous OCR SIS-027 result.

The FOT supported a 34m UPL demo pass with Station D34 on 01/22/02.  The
FOT sent a total of forty-three (43) commands to the Spacecraft during
the one hour and fifteen minute support.  As with the October 2001 34m
UPL demo pass with DSS-24, the command data accountability section in
the monitor block data was not valid; this is different from what is
currently received during nominal 34m supports.  Also in a nominal pass,
commands are rarely transmitted twice.  For this demo pass, two commands
were transmitted twice unexpectedly.  After completion of the planned
FOT activities DSS-34 asked if the FOT could send several no_op commands
to verify a change made in the command system.  A total of 16 no_op
commands were sent to the spacecraft;  all no_op commands were
verified.  During the postpass debrief, DSS-34 stated that a verify mode
needs to be disabled at BOT and on several occasions they got the error
message "Critical - Communication with POCC broken".  DR #C100841 was
opened for these items.  Additional 34m UPL demos will be scheduled as
resources are available.

Anomalies:
01/17/02  AR# G02-0008  At the start of the support the FOT noticed that
the mission was running slowly and in the midst of commanding the
spacecraft, the displays crashed on workstation3.  The FOT adhered to
FOT contingency policy and the impact was minimal.  Following the
support, the FOT investigated the cause of the crash.  The FOT found
several extraneous processes owned by the automation account running on
the realtime string.  A meeting was held between the FOT and automation
team to clarify the guidelines for development.

01/18/02  AR# G02-0009  FOT experienced ~9 minute telemetry dropout when
Isis processes shut down.  IP NOC contacted and informed FOT that they
were currently working with the IMAGE MOC.  All affected SSR data was
redumped.

01/20/02  AR# G02-0010  FOT unable to configure string 1 for realtime
operations.  FOT escalations procedures followed and TSMs notified.  FOT
failed over to string 2 and configured it to support the realtime
support.  No problems experienced with string 2 during the support.  TSM
contacted NASCOM who informed him that they were having intermittent
network dropouts.  Block history file replay performed to update DPS.

01/21/02  AR# G02-0011  Closed Network problems continued with string
1.  FOT unable to configure string 1 to support realtime pass.  IP NOC
and TSMs notified.  FOT escalations procedures followed.  String 2
configured and used to take realtime support.  TSM later reported to FOT
that the problem appeared to have been resolved at ~2200 on DOY 021.  No
specific information received as to the cause of the network problems.

01/22/02  AR# G02-0012  FOT noticed the spacecraft receiver AGC drop
each time a command was sent, though all commands were verified.
Station 16 contacted;  asked to monitor the command system.  D16 noticed
that the command modulation index spiked from the nominal .86 radians to
4.8.  FOT gave station go ahead to reconfigure system.  A no_op command
was sent and verified.  No further command problems experienced during
the support.

01/22/02  AR# G02-0017 Unknown command source  Station D16 contacted
station during the support (~1752) and queried whether FOT was
experiencing problems commanding.  The FOT was not commanding at the
time.  D16 said that they were receiving commands from somewhere.
~18:08 FOT finished commanding for the day and asked D16 if they found
the source of the commanding.  They said the source was 91 (91dec =
DSS-06 (DTF-21 70m) from OPS-6-21A).

01/22/02  AR# G02-0014 FOT locked out of the spacecraft during 34m UPL
demo.  FOT failed to synchronize the ground frame sequence number with
the spacecraft report value prior to issuing first command.  Escalation
procedures followed;  /Unlock command issued, /resync issued and the
demo continued.

01/24/02  AR# G02-0015  SISECHO page did not display all sections of the
dump.  The instrumenter monitored the execution of OCR SIS-027 and
received all data successfully.  One result was different than was
expected;  the instrumenter will investigate.

01/27/02  AR# G02-0016  FOT experienced ~3 minute telemetry dropout.
D16 contacted.  The station informed the FOT that there were SCP
problems.  No further problems experienced during the support (DR#
G100741).