ACE Weekly 05/19/2010 - 05/25/2010


All ACE spacecraft subsystems are performing nominally.

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

	Type        Attitude
	Date        05/21/2010
	DOY         141 2010
	Thrusters   2R 4R+ 4R-
	Duration    14:06 min
	Start       13:54:04z
	Stop        14:08:10z
	HGAStart    -7.98deg
	HGAStop      8.07deg
	SunStart    12.26deg
	SunStop      5.69deg
	SpinStart   5.0627rpm
	SpinStop    5.0666rpm
	Nutation     0.12deg
	Firing      72 pulses
	FuelUsed      0.2271lbs
	FuelRemain  136.3328lbs
	FinalSCMass 1370.593lbs

The next attitude maneuver is scheduled for Tuesday 06/01/2010.

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

None

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

Data Capture:  100%  DOY 136-143 2010

At the end of April (DOY 116 04/26/2010 23:45:00z), the SEPICA line
pressure (SSSLINEP) started fluctuating.  There are no limits for
SSSLINEP.  SSSLINEP data has been sent to Mark Popecki (SEPICA
instrumenter) for review.


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

DOY 139  05/19/2010  S-ACE-0505  G10-0026  ITOS tm_controller
ITOS was unable to process telemetry due to a "timeout reading from
tm_controller".  ITOS was restarted before beginning of track.  This
problem occurs approximately once every 2 weeks.  DR CDSID#00027515 has
been submitted and the ITOS developers expect this to be fixed in ITOS
805.
IMPACT:  Manual intervention required.  No delay in activities.


DOY 139  05/19/2010  S-ACE-0506  S10-0004  S3DPU_CONV_SEC_I RH Limit
S3DPU_CONV_SEC_I had a brief red high limit violation (RH > 480 mV).
	2010-139 16:28:25 - 16:28:26  482.406-490.25 mV
Mark Popecki was notified.
IMPACT: The last brief S3DPU_CONV_SEC_I red high limit violation was DOY
319 2006.


DOY 145  05/25/2010  S-ACE-0507  G10-0027  MUS CMD process terminated
The MMOC SLE (MUS) cmd process (ace-d45-cmd) terminated unexpectedly 2
minutes after beginning of track.  MUS did not generate an error
message.  The Ops Chief notified the FOT that no commands had reached
the station at 27 minutes after beginning of track.  The MUS CMD process
was restarted at 35 minutes after beginning of track.  Note: The MUS cmd
process dies on average once every 3 weeks, but usually in conjunction
with other problems.  It is rare that the MUS cmd process dies on its
own.
IMPACT:  Manual intervention required.  Activities delayed 35 minutes.


DOY 145  05/25/2010  S-ACE-0508  S10-0005  FAILCMDTFRM_CT increment
ITOS has a known issue (CDSID# 00027467) where an "OPEN port" directive
causes an ITOS proc to go through a WAIT.  After restarting MUS CMD with
an OPEN port (see AR#G10-0027), the ITOS proc was manually resumed.
However, the proc did not remain at the wait for command verification.
The 2nd and 3rd commands were sent before the 1st command.  The
spacecraft flagged the out-of-sequence commands.  ITOS then
retransmitted all 3 unverified commands in the proper order.
IMPACT:  Minimal.  The spacecraft flagged and discarded the
out-of-sequence commands.  ITOS automatically retransmitted the
commands.  The last command sequence error was DOY 295 2007
(AR#G07-0092) due to a dropped command by the ground network.