ACE Weekly 09/29/2010 - 10/04/2010

All ACE spacecraft subsystems are performing nominally.

Note:  ACE Weekly Reports will now cover the week ending on Monday
            The previous reports covered the week ending on Tuesday

========================================================================
Orbit/Attitude:

No maneuver was completed this week.  The next attitude maneuver is
scheduled for Friday 10/15/2010.

=======================================================================
OCRs:

None

========================================================================
Activities:

Data Capture:  100%  DOY 269-276 2010


DSN has requested a fourth Tracking, Telemetry & Command (TTC) Project
Interface Test (PIT).  Unfortunately, we cannot find antenna time for
the PIT.  The first PIT was successful when connecting through the RNS
which is the current operational route.  The last 2 PITs had been
unsuccessful when connecting through the future DCD route.  The
transition to the DCD is still a month or so away.  Options for more
testing are still being investigated.

========================================================================
Anomalies:

DOY 274  10/01/2010  S-ACE-0535  G10-0052  SLE CMDs Not Transmitted
DSS-54 had successfully transmitted commands at the beginning of the
pass (0830-0842z).  12 minutes after Beginning of Track, the ground
S-Band Exciter (used for uplink) had an error and all subsequent
commands were rejected by the station (DR#M105974).  This problem last
occurred 09/04/2010 (AR#G10-0044 DR#N106529).
IMPACT:  SSR playback had been started and completed without problems.
Final state-of-health commanding performed on the following day's pass.

Note on SLE CMDs Not Transmitted
This problem is similar to the problem SOHO has been experiencing with
DSN.  The problem can be fixed by disconnecting and reconnecting the SLE
FCLTU connection.  SOHO has updated their automation software to handle
this problem.  On DOY 280, DSN will test the CSET directive to see if
this breaks the bind and causes the MMOC to automatically reconnect.
Also, MOCR 222 has been submitted for the MMOC to automatically
disconnect and reconnect SLE FCLTU when commands are rejected by the
station.


DOY 276  10/03/2010  S-ACE-0536  G10-0053 ITOS tm_controller
ITOS was unable to process telemetry due to a "timeout reading from
tm_controller".  ITOS was restarted before beginning of track.  (DR
CDSID#00027515)
IMPACT:  Manual intervention required.  No delay in activities.

Update on ITOS tm_controller.
The FOT is investigating the possibility that ITOS DR CDSID#00027701
"event/postmaster process CPU usage" is a contributing factor to the
"timeout reading from tm_controller" problem.  All remote event windows
have been disconnected and this has significantly reduced the CPU usage
on the prime computer.  The prime computer's event log can be checked by
manually clicking the "connect" button on the remote computer and
clicking the "disconnect" button when done.  The CPU usage only becomes
a problem when the remote event window is connected over several days.


DOY 277  10/04/2010  S-ACE-0537  G10-0054  DSS-27 Transmitter RED
DSS-27 transmitter was declared RED earlier on DOY 277.  The transmitter
was expected to be out for the entire week, but the station was able to
provide an uplink 1.5 hours after the scheduled ACE Beginning Of Track.
(DR#G110598/G110597)
IMPACT:  If the DSS-27 transmitter was RED for the entire week, it would
have been very difficult to find antenna time (5 of the 7 ACE passes in
Week 40 were with DSS-27).  With the shortened pass on DOY 277, the
remaining 40 minutes of the SSR playback will be completed on the next
pass (40 minutes = 6.7 hours of playback data.)