July_31_1999_B.txt Shift B9. 

SOT Lead	Ed Kellogg
SpcCraft/Aspect	Mark Freeman
FOT/Sci liason	Andy Northrup
HRC		Ralph Kraft
ACIS 		Yousaf Butt

(Times will be given in GMT on day 212-13. not precise.)

I  PPP    SS          33       !!
I  P  P  S           3  3      !!
I  PPP    SS    --     3       !
I  P        S        3  3      
I  P      SS          33       !

EVENTS							PLAN	DONE	OBSID
--------------						----	----	-----
Start shift (9:19am EDT 31 July 1999)			1319	1319
ACIS collecting bias data				ongo	1704	62766
Vac monitor reading					1510	1530
SAP 6A025 to re-acquire fidlites			1512	1516
Continue monitoring ACA fidlites			1516-?
CAP 98, HRC hdwr cmds & ACIS SOP 61020_RADBELT_ENTRY 	1635	1704
Finish ACIS bias data run				1658	1704
ACIS radiation entry ATS to safe SIs			1658	1704
Change obsid for IPS-3 and earth scan 16		1705	1724	62484
HRC radiation entry ATS to safe SIs			1720	?
ACIS CAP 130A to do SW dump					1650
Earth scan 15						2040	deleted
Lost track on dimmest fidlite, #6				2104
Maneuver to burn angle, swap LGA, Diego->Canberra	2220	2220
IPS-3 BURN!!						2230	2232
End of burn						2256	2256
LOS at Canberra						2259	2259
AOS at Goldstone					
Earth scan 16				day 213		0040
End shift (9:19pm  EDT 31 July)		day 213		0119


NOTES/ISSUES/PROBLEMS
---------------------
SAP 6A025 to re-acquire fidlites with current reduced from 1.3 mA for
all to 0.4,0.6,1.1,1.3 mA for lites #3,4,5,6. The purpose of running
the fidlites at several reduced current settings is to assess the
effect of reduced brightness on susceptibility to loss of track from
charged particle events and possibly stray light, although we expect
to be pitched away from the sun for quite a while. At 2104, the tracking box
moved away from centering the dimmest fidlite; not
associated with a charged particle event.

Vac mon reading was 1.2e-5 torr.

We need to give more complete descriptions of what we are doing and
why we want it on CAPs we are writing, so that management can
understand better.

We could not see HRC radiation entry ATS to safe SIs because HRC was
already safed.

Flt note 121 " Attitude and Bias Update History" tells that over 204:16
to 211:06, the five attitude updates are about 0.5 - 1 degrees
each. The bias updates start at a few degrees/day and end up at ~0.1
degrees/day.

IPS burn 3, a tricky one because it's at perigee, appears nominal. We
had a handover from Diego to Canberra, and LGA swap, three attitude
maneuvers, and a ~20 minute burn, followed three minutes later by LOS
(loss of signal from Canberra). As of LOS, all indications are that
the burn was just what we wanted, with Chandra in good health.

As of 213:0030 TST mgr reports that the burn was very close to nominal
but a little hotter than expected. We will get the official word from
DSN in about three hours, next shift.

Shift A10 should schedule CAP 129 to re-acquire fidlites in ACA as
soon as possible.