 +_____________________________________________________________________
  AUTHOR:                                          SMS:  B08006     
  K. M. GJEVRE           BFS PROGRAM NOTE         __________________
 ____________________                              DATE:            
  ORG/PHONE:          OPS NOTE ( )  USER NOTE (X)   02/18/81        
  RI/DNY  922-3747         RELEASE NOTE ( )         REV A 11/04/91  
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  OI/FLIGHT EFFECTIVITY:          USER AFFECTED:                     
   STS-1 AND SUBS                 CREW (X)  GROUND ( )  DUMP ONLY ( )
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            MAJOR SOFTWARE AREA:             OPS MODES AFFECTED:     
 BSL( ) BSS(X) GNC(X) SEQ( ) SM/SP( ) IPL( )  1, 3                   
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  SOFTWARE SUB-AREA: DISP, SPEC                                       
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  PRINCIPAL FUNCTIONS: MG038101/3.3.8.2, STS83-0020D/4.2.10           
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  TITLE:  VALUE ASSOCIATED WITH BLANKED TARGET DATA                   
                                                                      
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  DESCRIPTION:                                                        
                                                                      
   AFTER A TARGET PARAMETER HAS BEEN ENTERED AND LOADED, A BLANK      
   VALUE FOR THAT PARAMETER ON THE BFS MANEUVER DISPLAY DOES NOT      
   MEAN A VALUE OF ZERO.  TARGET PARAMETERS WHICH HAVE BEEN           
   PREVIOUSLY ENTERED AND ARE CURRENTLY BLANK ON THE BFS MANEUVER     
   DISPLAY ACTUALLY CONTAIN THE VALUES WHICH WERE USED IN THE         
   PREVIOUS GUIDANCE CALCULATIONS.                                    
                                                                      
                                                                      
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 USER RESPONSE:                                                       
                                                                      
   TO ENSURE CORRECT TARGET DATA IS USED BY BFS, A COMPLETE           
   SET OF TARGET DATA MUST BE DISPLAYED ON THE BFS MANEUVER           
   DISPLAY.  THIS IS ACHIEVED BY AUTOMATIC PEG 4 TARGET SELECTION,    
   TARGET UPLINK, OR BY KEYBOARD ENTRY OF EACH ITEM.                  
                                                                      
                                                                      
                                                                      
                                                                      
                                                                      
                                                                      
                                                                      
                                                                      
                                                                      
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 CONCURRENCE:                           APPROVAL:                    
 RI:<S> J. AGRES           DATE 11/08/91                             
    ------------------         ---------                             
 FDSD: ROBERT N. HINSON    DATE 12/16/91                             
      ----------------         --------- S. N. HARDEE, JR.  12/19/91 
 PF MGR: MICHAEL J. JONES  DATE 12/18/91------------------- -------- 
        -----------------      --------- CHAIRMAN, SASCB      DATE   
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