NOAA-18, All Instrument, Solar Array Slew, 21 September 2005 - Issued: 20 Septembert 2005; 1400 UTC

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Topic*:
Solar Array Slew

*Date/Time(UTC) Message Issued:*
20 September 2005, 1400 UTC

*Satellite(s) Involved:*
NOAA-18

*Instrument(s) Involved:*
All Instruments

*Product(s) Involved/Affected:*
All Products

*Date/Time(UTC) of Initial Implementation:*
21 September 2005, Time 1600 UTC

*Details/Specifics of Change:*
Over a 24 hour period beginning on September 21 around 1600 UTC (orbit 1751) through September 22 around 1730 UTC (orbit 1766), SOCC will conduct two tests. A long slew of the solar array to change the signal characteristics of the array operations will be performed during each. Small pitch rate errors at the beginning and ending of the slew are expected.
SOCC is conducting this test to help in determining the cause of the pitch oscillations seen since launch. As stated in their test procedure, "The test involves commanding the array to slew speed where it will remain until it has completed a full revolution. We will test both slew diredtions. The slew period will be completed entirely during the darkness period of the orbit so that power levels and array health are unaffected. Temporary changes will also be made to CPU telemetry to gather additional data."

First test - reverse slew - 21 September, Jday 264, 1600 UTC, rev 1751, duration approximately 27.27 minutes

Second test - forward slew - 22 September, Jday 265, 1550 UTC, rev 1765, duration approximately 17.75 minutes

*Contact Person(s) Name/Email/Phone Number for Questions:*
Renee.Smith@noaa.gov 301-817-4117 SOCC operations support
Emily.Harrod@noaa.gov 301-457-5247 ext. 117 level 1B ops support

*Web site(s) that contain other relevant information (where applicable):*

http://www.osdpd.noaa.gov/PSB/PPP/PPP.html - History of level 1B notices
http://www.ssd.noaa.gov/PS/SATS/messages.html - All user notices
http://www.oso.noaa.gov/poesstatus/ - SOCC polar satellites status
http://www.oso.noaa.gov/daily-news/index.asp - SOCC morning reports

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*
* Emily D. Harrod
* NOAA/NESDIS/OSDPD/IPD
* Computer Operations Branch
* Pre-Product Processing Group
* E/SP11, Federal Building #4, room 0318
* 5200 Auth Road
* Suitland, Maryland 20746-4304
* USA
* voice 301-457-5247 ext 117
* fax 301-457-5199
* email Emily.Harrod@noaa.gov
*
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