To:sot_shift
from: Dan Schwartz
date: 13 Aug 99, 06:00am EDT
Subject: SOT shift report, Shift H22
--------
See http://asc.harvard.edu/acis/SOT_reports/sot-shift.html, or 
/proj/ascwww/AXAF/extra/science/htdocs/acis/SOT_reports/Aug_12_1999_H22.txt.

Shift H22 (A22) 
	Start at 225:03:30  GMT
		 = 11:30pm 12 Aug EDT
	End	   06:00am 13 Aug
   
SOT Lead	DAS
Spac/Aspect	RAC
FOT/Sci liason	EM
HRC		GA 
ACIS 		YB, 

(Times will be given in GMT on day 225. In general
times are rough, not precise.)

PLAN
Demonstrate dither mode
Demonstrate Normal point mode
Start Gyro scale factor and alignment determination.


EVENTS
OBSID is 62566 
~04:00 start SSR playback.
04:05   Initiate dither yrate 0.0047 z-rate = 0.010 
        amplitudes are 20 arcsec. 
04:30   End dither.
04:36   Set ACIS focal plane temperature to -100 deg C. Disable
	bakeout heater to see if focal plane heater can control.
05:27   CAP to turn-off fid lights prior to full field searches
05:39   start initial maneuver for gyro cal procedure.
05:40	ACIS stop science
New OBSID 62563
05:46	Start ACIS science run.  Long run containing all gyro 
	bias positions.
05:48   Complete initial gyro cal maneuver. At the actual planned
	SEP position, RA = 90, dec = -66.56
06:26   Do a zero length maneuver, then a full field search
06:32   full field search finds 8 stars.
06:41:30   start maneuver of 40 deg pitch.
07:03  At RA = 165.74   dec = -29.85  roll -150.0
	find 8 stars, 07:10
07:19  Slew 180 deg about sun line
08:04  Maneuver ends. At Ra=106.68   dec=56.88   roll=47.50
	acquire 8 stars.
08:30  maneuvering to -90 pitch position
08:50  End maneuver. At 304.09,  32.00
	Acquire 8 stars
09:01  Start maneuver 180 deg about anti-sun direction.

09:51  End maneuver, at 351.43, -60.13  roll 37.73.
	Acquire 8 stars, 5.8, 
10:03  Start Maneuver.  


NOTES/ISSUES/PROBLEMS
ACIS command load to go to -100 deg C has checksum error.
  We will stay at -90 deg C while it is investigated.
  Investigation showed checksum was okay, we proceed.

Brief gyro scale factor/misalignment procedure.

Vacuum monitor reading at 5.1 10^-6 torr.

OBSID's 62565 and 62564 were skipped.  They had been planned
   for the nudge mode operations, but had too much overhead
   of bias associated with stopping and starting science runs,
   so all the nudges were done under OBSID 62566 (as stated 
   in SOT report M22.)


-------------------------------------------------------
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 
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