To:sot_shift
from: Dan Schwartz
date: 05 Jan 00 , 12:00noon EST
Subject: SOT shift report, Shift L166
--------
See http://asc.harvard.edu/acis/SOT_reports/sot-shift.html, or 
/proj/ascwww/AXAF/extra/science/htdocs/acis/SOT_reports/Jan_05_2000_L166.txt.

Shift L166. 
	Start at 005:13:00  GMT
		 = 08:00am    05 Jan EST
	End	   12:00 noon 05 Jan
   
SOT Lead	DAS
Spac/Aspect	
FOT/Sci liason	
HRC		
ACIS 		

(Times will be given in GMT on day 005. In general
times are rough, not precise.)

PLAN
Continue running load DEC2699d. Do OBSID 752, ACIS-S observation of
middle aged pulsar PSR 1055-52. At 005:21:43 start CTI measurements
prior to belt entry.

Next Comms:
        005:14:00 to 16:00
        005:22:00 to 00:00
	006:05:00 to 06:30
	006:16:00 to 18:05
	006:22:00 to 00:00

EVENTS

Status at LOS, 005:08:29, was as follows:
       PCAD MODE              =       NPNT
       CONTROL LAW FLAG       =       NPNT
       Stars:                 =          5 
       FIDS                   =          3
       RA                     =    156.972 deg 
       DEC                    =    -43.923 deg
       ROLL                   =     47.046 deg
       Format                 =          2
       OBSID                  =        835 (NGC 3256)

       SIM FA                 =       -467
       SIM TSC                =      75623 (ACIS-S)
       HETG                   =        OUT (81.0 deg)
       LETG                   =        OUT (79.1 deg)
        HRC-S HV is ON 
        EPHIN:         A-Leak =   0.3640 mu-a
                       B-Leak =   0.0560 mu-a

13:26 Chandra descending at 124523 km.

AOS

Status at 005:14:51, was as follows:
       PCAD MODE              =       NPNT
       CONTROL LAW FLAG       =       NPNT
       Stars:                 =          5 
       FIDS                   =          3
       RA                     =    164.506 deg 
       DEC                    =    -52.470 deg
       ROLL                   =     52.200 deg
       Format                 =          2


       OBSID                  =        752 (PSR 1055-52)

       SIM FA                 =       -467
       SIM TSC                =      75623 (ACIS-S)
       HETG                   =        OUT (81.0 deg)
       LETG                   =        OUT (79.1 deg)
        HRC-S HV is ON 
        EPHIN:         A-Leak =   0.3680 mu-a
                       B-Leak =   0.0560 mu-a

	ACIS focal plane temperature reads -109.2
	Chandra descending through 119915 km

16:00 LOS. Status essentially unchanged from AOS.

NOTES/ISSUES/PROBLEMS
From the 9am status meeting:
	In last 24 hours, 3 supports, 3 successful data dumps,
uploaded next segment of DEC2699d. Only one more command segment is
needed to be uploaded to carry us to the end of the current schedule on 9 Jan.
	A meeting will be scheduled soon to review the final products
for uploading the continuous dither patch. Testing from 20 Dec has
been analyzed and was successful. In order to permanently upload the
patch we must get Level II board and IPI team consensus approval on our plan
for using continuous dither.  This plan has two steps (which might
occur simultaneously); first its use  without any changes to
our ground planning (i.e., with OFLS 7), and second how we will use
enhancements in OFLS 8 together with necessary characteristics and CSD
changes to take advantange of the extra efficiencies.
	VCDU rolled over to zero counts on 004:19:29:59.488058.
	Next eclipse season starts Feb 25. This will have more short
eclipses than last season, but no different procedures than we used
for the Fall season.
	IRU unit A, gyro number 2, has seen several more current jumps
(cf. shift report L75, 6 Oct 99). These are still well within the 
allowed limits. This causes changes in pitch and yaw
bias. A data package was sent to Kearfott and discussed with them
yesterday. Kearfott says the magnitudes of the jumps are larger than
they expect -- not seen in ground data. Kearfott/TRW recommends
staying on this unit and watching its behaviour. The values to 
be used as yellow and red limits will be reviewed. FOT is prepared to do
a switch to IRU unit B if necessary -- that would imply repeating the
scale factor and alignment calibration maneuvers done at the start of
observing on 1999 day 224-225. A followup telecon is planned for
Monday, Jan 10, at 4pm.  
	After his retirement from a 30 year career at NASA, Ron Felice
agreed to join the Chandra project to help us create a Flight
Operations Team and facility out of nothing. He has done this more
than successfully, leading us through launch and activation, and
providing a team with proven capabilities to resolve anomalies and
keep Chandra scheduled and operating.  He is therefore taking the
opportunity to retire again, leaving the FOT under the capable
direction of Leon McKendrick who will officially become FOT manager on
Jan 17. Ron will remain until the end of February as senior advisor to
aid the transition.


-------------------------------------------------------
Dan Schwartz,	MS #3
das@head-cfa.harvard.edu  
phone: (617)495-7232    FAX:   (617)495-7356
cell phone: (617)512-5627   
pager: 800-759-8352 PIN 1636502
       or e-mail 1636502@skytel.com 
-------------------------------------------------------