 +_____________________________________________________________________
 ] AUTHOR:            ]                             ] DR:              ]
 ] J. W. BRADBURY     ]    PASS PROGRAM NOTE        ]     101705       ]
 ]____________________]                             ]__________________]
 ] ORG/PHONE:         ] OPS NOTE ( )  USER NOTE (X) ] DATE: 08/24/87   ]
 ] IBM/282-7368       ]      RELEASE NOTE( )        ]   REV 08/03/89   ]
 ]____________________]_____________________________]__________________]
 ] OI/FLIGHT EFFECTIVITY:        ]  USER AFFECTED:                     ]
 ]  OI8B AND SUBS                ]  CREW (X)  GROUND (X)  DUMP ONLY ( )]
 ]_______________________________]_____________________________________]
 ]        MAJOR SOFTWARE AREA:       ] OPS MODES AFFECTED:             ]
 ]SSW ( )  GNC (X)  VU ( )  SM/PL ( )] G1                              ]
 ]_____________________________________________________________________]
 ] SOFTWARE SUB-AREA: DYNAMICS, GUID, FCS, ILOAD                       ]
 ]_____________________________________________________________________]
 ] PRINCIPAL FUNCTIONS: 4.1, 4.175                                     ]
 ]_____________________________________________________________________]
 ] TITLE:                                                              ]
 ]        MULTIPLE SSME FAILURE RESULTS IN PITCH COMMAND OSCILLATIONS  ]
 ]_____________________________________________________________________]
 ] DESCRIPTION:                                                        ]
 ]                                                                     ]
 ] OSCILLATING PITCH COMMANDS ARE ISSUED BY THE AUTO-LOFT LOGIC FOR    ]
 ] MULTIPLE SSME FAILURES DURING FIRST STAGE FLIGHT.  THE OSCILLATIONS ]
 ] RESULT FROM TRANSPORT LAGS ON PITCH ERROR, ALPHA, AND ENGINE OUT    ]
 ] NOTIFICATION TO GUIDANCE, AND GUIDANCE COMMANDS TO THE ENGINES.     ]
 ]                                                                     ]
 ] ILOAD CONSTRAINTS WERE ADDED BY CR 89638 FOR OI8C AND SUBS.  THE    ]
 ] MAGNITUDE OF THE OSCILLATIONS ARE REDUCED WITH ILOADS MEETING THESE ]
 ] CONSTRAINTS.                                                        ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]_____________________________________________________________________]
 ]USER RESPONSE:                                                       ]
 ]                                                                     ]
 ]  BE AWARE OF THIS BEHAVIOR.                                         ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]_____________________________________________________________________]
 ]CONCURRENCE:                           ]APPROVAL:                    ]
 ]IBM: WYATT COOPER         DATE 09/26/89]                             ]
 ]    --------------------      ---------]                             ]
 ]SSD: SAM ANKNEY           DATE 09/27/89]                             ]
 ]    --------------------      ---------] M.C. GREMILLION    10/05/89 ]
 ]PF MGR:DALLAS IVES        DATE 09/29/89]------------------- -------- ]
 ]       -----------------      ---------] CHAIRMAN, SASCB      DATE   ]
 ]       KIRK SHIREMAN      DATE 09/29/89]------------------- -------- ]
 ]       -----------------      ---------]                             ]
 ]_______________________________________]_____________________________]
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