To:sot_shift
from: Dan Schwartz
date: 12 Aug 08, 12:00noon EDT
Subject: SOT shift report 2008-08-12 L3309
--------
See http://asc.harvard.edu/acis/SOT_reports/sot-shift.html, or 
/proj/web-cxc/htdocs/acis/SOT_reports/Aug_12_2008_L3309.txt.

Shift L3309. 
	Start at 225:12:00  GMT
		 = 08:00am    12 Aug EDT
	End	   10:00am    12 Aug
   
SOT Lead	DAS
(Times will be given in GMT on day 225.)

PLAN
----
Load AUG1108A has been stopped, Chandra is in Normal Sun Mode. We are
looking at back-orbit data and using ASVT to diagnose how this happened.

Next Comms:
Current comm extended to 1435. Looking for extra comm time this
afternoon and evening.
Scheduled:
225/1910-2200   1950 2050 DSS-46    CANBERRA   1550-1650 EDT, Tue 12 Aug
226/0245-0500   0345 0445 DSS-54    MADRID     2345-0045 EDT, Tue 12 Aug
226/1000-1215   1100 1200 DSS-27    GOLDSTONE  0700-0800 EDT, Wed 13 Aug
226/2120-2335   2220 2320 DSS-54    MADRID     1820-1920 EDT, Wed 13 Aug
227/0345-0600   0445 0545 DSS-24    GOLDSTONE  0045-0145 EDT, Thu 14 Aug
227/1035-1325   1115 1315 DSS-66    MADRID     0715-0915 EDT, Thu 14 Aug

Orbital events:
225:18:14:15.340   1245  EPERIGEE  ORBIT PERIGEE 
227:01:59:15.397   1246  EAPOGEE   ORBIT APOGEE
228:09:43:23.984   1246  EPERIGEE  ORBIT PERIGEE   
229:17:28:48.582   1247  EAPOGEE   ORBIT APOGEE    
231:01:12:57.636   1247  EPERIGEE  ORBIT PERIGEE      
232:08:57:45.067   1248  EAPOGEE   ORBIT APOGEE  
233:16:42:04.424   1248  EPERIGEE  ORBIT PERIGEE
235:00:25:50.949   1249  EAPOGEE   ORBIT APOGEE 

EVENTS
------
Status at AOS, 225:10:44, was as follows:
       PCAD MODE              =       NSUN
       CONTROL LAW FLAG       =       SPNT
       Stars:                 =           
       FIDS                   =          
       RA                     =    202.855 deg 
       Dec                    =    -61.847 deg
       ROLL                   =    237.048 deg
       Format                 =          4
       OBSID                  =      57652
       SIM FA                 =       -535
       SIM TSC                =     -99615 (ACIS-IHRC-S)
       DITHER		      =	      ENAB 
       HETG                   =        OUT (79.09 deg)
       LETG                   =        OUT (77.21 deg)
        HRC-S HV is ON 
       EPHIN Geom             =       SMAL
	     E150	      =	      38.1
	     E300	      =	       2.3
             E1300            =        5.6           LT 20.0 (RADMON
             P4GM             =        0.1           LT 300. Disabled)
             P41GM            =        0.0           LT 8.47
Descending through 73219 km. 
EPH temp: 93.79 degF   EPH 27V: 

12:13  Switch to format 2 to get some ACIS data. 
ACIS notes the BEP had rebooted, presumed due to SCS107 executing
while ACIS was computing bias.

EPH 27V   26.84 

12:54  Return to format 4.

14:02  Status is essentially unchanged. Altitude is 50535D. High EPHIN
electron rates are saturating the P4GM channel. 

NOTES/ISSUES/PROBLEMS
At AOS (10:44) Chandra was in an unexpected Normal Sun Mode
state. Error logs indicated errors starting at 09:26 with an MC
resynch to SH error. Transition to NSM at 10:07 following end of a
maneuver at 10:03:41.010. Maneuver started at 09:21:49.521. Working
hypothesis is that an CTU or IU reset caused timing errors which caused the
maneuver to end at the wrong place, and since it didn't find guide
stars and since the sun was not in the fine sun sensor field of view
Chandra went directly to NSM (by-passing the bright star hold mode). 

From the 9am status meeting:
Three supports over the past day, no issues.
AUG1808B products out for an email review by 2pm today.
In normal sun mode. Waiting for dump data processing. Recovery needs
to include rebooting ACIS BEP and starting ACIS housekeeping run. 

Further telecon to be announced after looking at back-orbit data and 
running ASVT.
Email from Juda announces this telecon for
11am EDT on 877-521-0441 111165#


Quick look data:
OBSID   Target           Time                        Comment
-----   ------           --------------              -------

-------------------------------------------------------
Dan Schwartz,	MS #3
das@head-cfa.harvard.edu  
phone: (617)495-7232   
cell phone: (617)512-5627   
pager: email to 6175125627@vtext.com
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