 +_____________________________________________________________________
 ] AUTHOR:            ]                             ] SMS:  B02782     ]
 ] R. LOHMANN         ]    BFS PROGRAM NOTE         ]                  ]
 ]____________________]                             ]__________________]
 ] ORG/PHONE:         ] OPS NOTE ( )  USER NOTE (X) ] DATE:  9/21/83   ]
 ] RI/DNY X-4164      ]      RELEASE NOTE ( )       ] MOD A: 4/23/90   ]
 ]____________________]_____________________________]__________________]
 ] OI/FLIGHT EFFECTIVITY:        ]  USER AFFECTED:                     ]
 ]  9.21 AND SUBS                ]  CREW (X)  GROUND (X)  DUMP ONLY ( )]
 ]_______________________________]_____________________________________]
 ]           MAJOR SOFTWARE AREA:            ] OPS MODES AFFECTED:     ]
 ]BSL( ) BSS( ) GNC( ) SEQ(X) SM/SP( ) IPL( )] 0, 1, 3, 6              ]
 ]_____________________________________________________________________]
 ] SOFTWARE SUB-AREA:  RCS, DISP, FDA                                  ]
 ]_____________________________________________________________________]
 ] PRINCIPAL FUNCTIONS: MG038120/3.3.1.10                              ]
 ]_____________________________________________________________________]
 ] TITLE:  NEGATIVE RCS QUANTITY VALUES                                ]
 ]         AND LEAK ALERTS - BFS                                       ]
 ]_____________________________________________________________________]
 ] DESCRIPTION:                                                        ]
 ]                                                                     ]
 ]  NEGATIVE RCS OXIDIZER AND FUEL QUANTITY READINGS MAY APPEAR ON THE ]
 ]  BFS GNC  SYSTEM  SUMMARY 2  DISPLAY. FALSE LEAK ALERTS MAY ALSO    ]
 ]  OCCUR AT THIS AND OTHER TIMES DUE TO PVT (PRESSURE, VOLUME, AND    ]
 ]  TEMPERATURE) CALCULATION LIMITATIONS.                              ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]_____________________________________________________________________]
 ]USER RESPONSE:                                                       ]
 ]                                                                     ]
 ]  THE USER SHOULD BE AWARE THAT THE PVT CALCULATION IS DESIGNED TO   ]
 ]  ESTIMATE THE AMOUNT OF LIQUID PROPELLANT REMAINING TO BE USED. A   ]
 ]  SMALL AMOUNT OF PROPELLANT REMAINS IN THE TANK ONCE THE INDICATED  ]
 ]  QUANTITIES REACH ZERO. THE QUANTITY INDICATION CONTINUES TO        ]
 ]  ACCURATELY REFLECT USAGE PAST ZERO UNTIL GAS BREAK OCCURS. NEGATIVE]
 ]  QUANTITY INDICATIONS PRIOR TO GAS BREAK AND THE LEAK ALERT AT GAS  ]
 ]  BREAK ARE USEABLE INFORMATION TO THE CREW. SUBSEQUENT LEAK ALERTS  ]
 ]  MAY OCCUR BUT ARE UNLIKELY AND MEANINGLESS. MULTIPLE LEAK ALERTS   ]
 ]  MAY OCCUR AT ANY TIME WHEN A DATA VALUE USED IN THE CALCULATION    ]
 ]  TOGGLES SO AS TO REPEATEDLY CAUSE THE LEAK DETECTION THRESHOLD     ]
 ]  TO BE EXCEEDED. THIS CAN OCCUR IN FLIGHT WHEN A SLOW LEAK HAS      ]
 ]  CAUSED THE QUANTITY DIFFERENCE TO LINGER AT THE I-LOADED LIMIT, OR ]
 ]  ON THE GROUND WHEN THE RCS SYSTEM HAS NOT BEEN FULLY SERVICED AND  ]
 ]  PROPERLY INITIALIZED.                                              ]
 ]_____________________________________________________________________]
 ]CONCURRENCE:                           ]APPROVAL:                    ]
 ]RI:<S> C. PURTELL         DATE 05/01/90]                             ]
 ]   ------------------         ---------]                             ]
 ]FDSD:  SAM ANKNEY         DATE 05/23/90]                             ]
 ]    -----------------         ---------]DARREL E. STAMPER   05/24/90 ]
 ]PF MGR:  D. W. MAY        DATE 05/23/90]------------------- -------- ]
 ]       -----------------      ---------] CHAIRMAN, SASCB      DATE   ]
 ]_____________________________________________________________________]
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