 +_____________________________________________________________________
  AUTHOR:                                          SMS: B27041      
   C. WANG, J. KIEL      BFS PROGRAM NOTE          DR:  108577      
 ____________________                             __________________
  ORG/PHONE:          OPS NOTE (X)  USER NOTE ( )  DATE: 5/13/93    
  RID/(310)922-3714        RELEASE NOTE ( )        REV A 02/05/96   
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  OI/FLIGHT EFFECTIVITY:          USER AFFECTED:                     
    OI-21 through OI-25           CREW (X)  GROUND (X)  DUMP ONLY ( )
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            MAJOR SOFTWARE AREA:             OPS MODES AFFECTED:     
 BSL( ) BSS( ) GNC(X) SEQ(X) SM/SP( ) IPL( )         1               
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  SOFTWARE SUB-AREA:   RCS_CMD_HIP                                    
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  PRINCIPAL FUNCTIONS:  MG038106/3.2.5.5.3 RCS Command HIP            
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  TITLE: RCS Jet Failure on Engagement during PASS                    
         Return-to-Normal OMS Interconnect Dump                       
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  DESCRIPTION:                                                        
                                                                      
  The scenario that led to +x AFT RCS jet FAIL-OFF is as follows.     
                                                                      
  PASS was made to fail during OMS fuel dump sequence after closing   
  OMS crossfeed valves but before opening RCS isolation valves.  Time 
  gap between these two events is 1.6 seconds.  Furthermore, before   
  the PASS failure, there was a commfault that BFS detected but PASS  
  did not.  It resulted in prolonging the dump time for BFS.          
                                                                      
  Consequently, when BFS was engaged, RCS jet firing flag S_RCS_IGN   
  was ON, causing RCS_CMD_HIP to fire jets.  Since RCS isolation      
  valves were still closed, no propellant was available and thus      
  the jet FAIL-OFF error was generated.                               
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  USER RESPONSE:                                                      
                                                                      
  If this complicated scenario led to the above described RCS jet     
  FAIL-OFF error, the user should recycle RCS jet manifolds which     
  will reset the RCS jet error status.  This will enable the user     
  to detect any subsequent RCS jet failure again.                     
                                                                      
                                                                      
                                                                      
                                                                      
                                                                      
 _____________________________________________________________________
 CONCURRENCE:                           APPROVAL:                    
 RI: <s> d. corbin         DATE 01/22/97                             
     --------------------      ---------                             
 ASD:   ERIC C. BINGHAM    DATE 02/18/97                             
     --------------------      --------- darrell r. stamper 03/07/97 
 PF MGR:  J. P. RUPPERT    DATE 03/05/97------------------- -------- 
        -----------------      --------- CHAIRMAN, SASCB      DATE   
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