Sep_16_1999_H56.txt Shift H56
        Start at 1999:260:02:00 GMT
                = 1999 Sep 16 10:00pm EDT
        End       1999 Sep 17 04:00am EDT
        http://asc.harvard.edu/acis/SOT_reports/sot-shift.html
   
SOT Lead	Bill Podgorski
SOT SC/ACA
FOT-SI		
HRC-SI          Mike Juda
ACIS-SI		Yousaf Butt, Fred Baganoff


Status/Plans:
------------
  - Running P14b load
  - Start radiation belt transition(OBSID 62384)
  - Eclipse

      
EVENTS							    DONE	OBSID
--------------						    ----	-----
Start Shift                                             260:0200        62384 - P14b load
------ Real time contact DSS-54 (Madrid) ------
Start eclipse                                           260:0250
End eclipse                                             260:0305
   (See note 1)
LOS DSS-54                                              260:0330  
----- Out of Contact------
AOS DSS-42                                              260:0700
----- Real time------ 
Confirm configuration                                   260:0710
   (see note 2 below)
LOS DSS-42                                              260:0800
----- Out of Contact------
End shift                                               260:1000


NOTES/ISSUES/PROBLEMS 
--------------------- 

1) Eclipse performance was close to nominal, with the peak bus voltage slightly
   above prediction but within expected error bar. This eclipse was a "medium 
   eclipse" from penumbra to penumbra. 


2) Prior to loss of COMM the S/C configuration was as follows:

       PCAD MODE= NPT
       Stars:   = 5
       FIDS     = 0
       RA       = 84.00000
       DEC      =  5.50000
       ROLL     = 92.488639
       Format   = 2
       OBSID    = 62384
       SIM FA   = -467
       SIM TSC  = 75615 (ACIS-S)
       HETG     = 7.8, 6.7 degrees
       LETG     = 81.7, 79.8
       ACIS:    = Video boards and Front End Processors OFF
       HRC:     = S HV OFF, I HV OFF, Shield HV OFF
       Tel MCE  = All voltages OFF

   Upon AOS at 260:0700 the configuration was the same as above. 


3) A review of the P15 load was held at 11:30pm EDT. During the review several
   issues were discussed. The warning messages output by the acacheck script
   were deemed acceptable by Rob Cameron and Eric Martin. HETG grating retraction
   was to take place at 260:1832. Flight software will be asked to review the
   state of the grating flags from the last memory dump. ACIS had not reviewed
   the load as of the time of the telecon, and they were asked to review it
   prior to uploading during the 0700 to 0800 COMM.

   After the telecon Fred Baganoff reviewed the load for ACIS. He initially 
   looked at the first two observations. He found that the first observation,
   a GTO observation of A401 using ACIS, had an unusual specification of ACIS
   chips (I2, I3, S2, S3, S4 and S5). After some time spent on the phone with
   CXC mission planners (Pat Slane talking to Paul Green) it was determined that 
   this was incorrect. The correct chipset would be (I0, I1, I2, I3, S2 and S3). 
   However, the power configuration and parameter block were correct for the
   incorrect set of chips. 

   The flight director, M. LeBlanc, was called. Two options were discussed:

        a) Rebuild the load for uplink starting at the 260:1835 COMM period,
           with a delayed start time. 
        b) Go with the load as is and stop the ACIS science run early in the
           COMM period. Upload (via real-time CAP) the correct ACIS configuration
           and restart the ACIS science run. 

   The first option was selected by the FD. Ken Gage was called and informed 
   the decision. Also, Royce Buehler was called. He identified an available
   parameter block which has the correct chipset turned on. 

   The actions for tonight and tomorrow are for Fred to complete the review
   of the entire P15 load and for Royce (on Friday morning) to give the
   parameter block to Ken for use in rebuilding the P15 load, prior to the
   260:1835 COMM. 

4) COMM for the next two days is as follows(all GMT):

        260:1825 - 261:0050  DSS-61
        261:0930 - 261:1210  DSS-46
        261:1900 - 261:2200  DSS-66
        261:2145 - 262:0000  DSS-54
        262:0600 - 262:0800  DSS-24
        262:1400 - 262:1900  DSS-46
        262:2330 - 263:0130  DSS-27