Thursday, October 19, 1995

USA-68

 1990-105A


Block 5D-2 S-10 (DMSP 21544, USA 68) was launched on 1990 Dec 1 by Atlas E from Vandenberg. The Star 37S kick stage underperformed when the nozzle failed during the last second of the burn, and S-10 (now F-10) entered an elliptical orbit. The hydrazine was used to partly correct the orbit, but was depleted in the operation. Initially tumbling, the spacecraft attained three-axis stabilization by the second orbit. The shock of the kick motor failure caused the solar array initially to deploy only partly, but later on rev 2 it popped fully open. The spacecraft operated for 4 years.


DMSP 21544 (S-10) 
 

DateTimeEventOrbit  

1990 Dec 1  1557:35  Launch by Atlas E  V SLC3W 
 1559:39 T+2:04 Booster sep
 1559:59  T+2:24 Fairing sep
 1603:00 T+5:21 SECO 
 1603  Atlas sep 
 1609  T+10:27? Star 37S burn 43.4s 
 1610 Star 37S nozzle failed T+42s  610 x 850 x98.9 
 1610 Hydrazine burn, 32 m/s  
   100.71 734 x 850 x 98.9  
1990 Dec?   OLS cover sep 
1991 Apr 8    100.64 731 x 846 x 98.8 
1993 Aug   Still operational
1994 Sep 26   end of ops
1994 Dec?   OLS off 
1995 Aug 11    100.52 725 x 840 x 98.6 

No comments:

Post a Comment

May 13,2026

  https://planet4589.org/space/jsr/back/news.855.txt