 +_____________________________________________________________________
 ] AUTHOR:            ]                             ] SMS: B22554      ]
 ]    R. SAUSER       ]    BFS PROGRAM NOTE         ] DR:  106078      ]
 ]____________________]                             ]__________________]
 ] ORG/PHONE:         ] OPS NOTE ( )  USER NOTE (X) ] DATE: 10/9/90    ]
 ]    922-4164        ]      RELEASE NOTE ( )       ]                  ]
 ]____________________]_____________________________]__________________]
 ] OI/FLIGHT EFFECTIVITY:        ]  USER AFFECTED:                     ]
 ]    OI-8C AND SUBS             ]  CREW (X)  GROUND (X)  DUMP ONLY ( )]
 ]_______________________________]_____________________________________]
 ]           MAJOR SOFTWARE AREA:            ] OPS MODES AFFECTED:     ]
 ]BSL( ) BSS( ) GNC( ) SEQ(X) SM/SP( ) IPL( )]    1,3,6                ]
 ]_____________________________________________________________________]
 ] SOFTWARE SUB-AREA:  ABORT                                           ]
 ]_____________________________________________________________________]
 ] PRINCIPAL FUNCTIONS:  MG038120/3.3.1.13                             ]
 ]_____________________________________________________________________]
 ] TITLE:                                                              ]
 ]         PASS FAILURE DURING OMS/RCS RECONFIGURATION.                ]
 ]_____________________________________________________________________]
 ] DESCRIPTION:                                                        ]
 ]                                                                     ]
 ] TWO SCENARIOS ARE KNOWN TO EXIST DURING THE OMS/RCS                 ]
 ] INTERCONNECT BOTH OF WHICH COULD CAUSE BFS TO STACK VALVE           ]
 ] COMMANDS WHICH IT WILL SALVO OUT UPON ENGAGEMENT AND WHICH MAY      ]
 ] RESULT IN A POWER OVERLOAD CAUSING THE SSME CONTROLLER TO SHUT      ]
 ] DOWN ALL RUNNING ENGINES AND A POSSIBLE LOSS OF AC-POWERED          ]
 ] SYSTEMS.                                                            ]
 ]                                                                     ]
 ] IN THE FIRST SCENARIO, IF PASS FAILS AND BFS ENTERS A STAND-ALONE   ]
 ] DURING THE INTERCONNECT, BFS WILL STACK VALVE COMMANDS WHICH IT WILL]
 ] SALVO OUT UPON ENGAGEMENT.                                          ]
 ]                                                                     ]
 ] IN THE SECOND SCENARIO, SINCE PASS AND BFS ARE NOT GUARANTEED TO RUN]
 ] ON THE SAME CYCLE, A MOMENTARY COMFAULT MAY BE SEEN BY ONE SYSTEM   ]
 ] AND NOT THE OTHER CAUSING THE TWO SYSTEMS TO CONFIGURE THE INTER-   ]
 ] CONNECT DIFFERENTLY WHICH MAY RESULT IN A SALVO OF VALVE COMMANDS   ]
 ] UPON BFS ENGAGEMENT.                                                ]
 ]_____________________________________________________________________]
 ] USER RESPONSE:                                                      ]
 ]                                                                     ]
 ] THERE IS NO ACCEPTABLE USER WORKAROUND FOR THESE PROBLEMS.          ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]_____________________________________________________________________]
 ]CONCURRENCE:                           ]APPROVAL:                    ]
 ]RI: <S> C. PURTELL        DATE 10/11/90]                             ]
 ]    --------------------      ---------]                             ]
 ]FDSD:   SAM ANKNEY        DATE 10/25/90]                             ]
 ]     -------------------      ---------] DARRELL E. STAMPER 10/26/90 ]
 ]PF MGR:KENNETH R. KROLL   DATE 10/26/90]------------------- -------- ]
 ]       -----------------      ---------] CHAIRMAN, SASCB      DATE   ]
 ]_____________________________________________________________________]
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