Saturday, January 18, 1997

ATS 5

  1969-069A


ATS E (Applications Technology Satellite 5) was the third successful ATS. Launch by Atlas Centaur was at 1101 UT on 1969 Aug 12. Because of its heavier mass, ATS-5 needed a more elliptical parking orbit and a shorter coast time. The satellite was inserted into geostationary transfer orbit and fired its SR-28-3 apogee motor (serial number was either Z-4 or Z-6). The AKM was fired at first apogee instead of the planned second because of an attitude control anomaly. The apogee motor was to have been ejected 90s later to improve stability characteristics, but the spacecraft went into a flat spin and the ejection was aborted. ATS 5 was allowed to drift into view of the Rosman ground control station, and was maneuvered so that the spin was around the correct axis, but upside down. The motor was jettisoned on Sep 5. It impacted the solar array during ejection and caused minor damage. Because ATS-5 was spinning in the wrong direction, the yo-yo system could not be used and the gravity gradient booms could not be deployed. The spacecraft remained at 105 deg W until 1978 when it was moved to 70W; in 1984 it ran out of stationkeeping fuel and was moved off station. Its orbit was raised sometime in the months following Apr 1984.


ATS 5 
 

DateTimeEventOrbit  

1969 Aug 12  1101:04 Launch by Atlas Centaur 
  T+2:32 BECO 
  T+2:35 Booster sep 
  T+3:21 panel jettison, 520 kg. 
  T+3:53 Fairing sep, 970 kg 
  T+4:10 SECO 
  T+4:13 Atlas sep 
  T+4:23 Centaur burn 
 1111  T+10:39 Centaur MECO 25 min coast 142.80 181 x 5158 x 26.79 
 1136 T+35:43 Centaur MES2 1:11 
 1137 T+36:54 Centaur MECO2  686.46 2147 x 36645 x 17.60 (Delta rpt) 
 1140 T+39:09 Centaur sep 
  T+46:09 Centaur blowdown, pos-sep burn H2O2, 49s 
  T+46:58 Centaur post-sep H2O2 off  
  T+46:59 Centaur venting703.7 2187 x 37471 x 17.59 (AC) 
 1150? ATS-5 spun up to 95 rpm 
 1710?  AKM 44s burn  1463.97 35763 x 36901 x 2.7 (PLR No2) 
   35784 x 36908 x 2.62  
   35688 x 36809 x 2.62 (TMX-2383) 
 1710   1416.43 34844 x 35956 x 2.7 GEO 90.5E+5.0W 
1969 Aug 12   attitude control issues
1969 Aug 17 attitude control recovered 
1969 Sep 5   AKM jettison
1969 Sep 5   Yo-yo despin 
1969 Oct 2    1435.99 35778 x 35791 x 2.6 GEO 106.6W 
1970 Aug 2    1436.12 35726 x 35847 x 1.7 GEO 104.9W 
1971 May 31    1436.22 35724 x 35853 x 1.0 GEO 105.1W 
1974 May 3    GEO 105.4W 
1975 Sep 17    GEO 104.9W 
1976 Mar 15    GEO 104.9W 
1977 Jan 10    GEO 105.4W 
1977 Feb?   Move out 
1977 Feb 18    1434.83 35731 x 35792 x 3.8 GEO 94.8W+0.3W/d 
1977 May   Move in 
1977 May 25    1435.94 35773 x 35793 x 4.0 GEO 70.3W 
1978 Oct 18    1436.00 35780 x 35788 x 5.0 GEO 69.4W 
1980 Feb 28    1436.12 35773 x 35800 x 5.9 GEO 69.8W 
1982 Jul 12    1435.98 35774 x 35794 x 7.3 GEO 68.8W 
1982 Nov 19   Drift 1436.16 35774 x 35800 x 7.6 GEO 69.7W+0.02 
1983 Jan 11    1435.90 35775 x 35789 x 7.7 GEO 70.1W+0.04 
1983 Feb 9   Move out 1435.45 35755 x 35792 x 7.7 GEO 61.3W+0.15W 
1983 Mar 13   Move in  1435.76 35751 x 35808 x 7.8 GEO 53.1W 
1983 Apr 27    1435.90 35741 x 35811 x 7.8 GEO 50.5W+0.04 
1983 Aug?   Move out 
1983 Sep 9    1435.54 35727 x 35823 x 8.0 GEO 77.5W+0.1W 
1983 Nov 28    1435.98 35735 x 35833 x 8.2 GEO 71.4W+0.02 

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