 +_____________________________________________________________________
 ] AUTHOR:            ]                             ] DR:              ]
 ] P. ROATH           ]    PASS PROGRAM NOTE        ]   46505          ]
 ]____________________]                             ]__________________]
 ] ORG/PHONE:         ] OPS NOTE ( )  USER NOTE (X) ] DATE: SEPT. 1987 ]
 ] VER/282-8840       ]      RELEASE NOTE( )        ]                  ]
 ]____________________]_____________________________]__________________]
 ] OI/FLIGHT EFFECTIVITY:        ]  USER AFFECTED:                     ]
 ] REL 19 AND SUBS               ]  CREW (X)  GROUND ( )  DUMP ONLY ( )]
 ]_______________________________]_____________________________________]
 ]        MAJOR SOFTWARE AREA:       ] OPS MODES AFFECTED:             ]
 ]SSW ( )  GNC (X)  VU ( )  SM/PL ( )] G1                              ]
 ]_____________________________________________________________________]
 ] SOFTWARE SUB-AREA:  ADI                                             ]
 ]_____________________________________________________________________]
 ] PRINCIPAL FUNCTIONS: 4.168                                          ]
 ]_____________________________________________________________________]
 ] TITLE:                                                              ]
 ] SPIKE IN ADI ERROR NEEDLE PITCH AXIS                                ]
 ]_____________________________________________________________________]
 ] DESCRIPTION:                                                        ]
 ]                                                                     ]
 ] WHEN BOTH OMS ENGINES ARE SHUT OFF PREMATURELY VIA ARM/PRESS SWITCH ]
 ] AND GUIDANCE IS NOT YET CONVERGED TO RCS SOLUTION, COMMANDED BODY   ]
 ] ATTITUDE TASK USES LAST OMS THRUST DIRECTION VALUE AND I-LOADED     ]
 ] RCS TRIM VALUE, WHICH WILL CAUSE APPROXIMATELY A 6 DEGREE SPIKE IN  ]
 ] ADI ERROR NEEDLE PITCH AXIS AND PEG OUT TO 10 DEGREES IN YAW. NOW   ]
 ] WHEN GUIDANCE CONVERGES (IN APPROXIMATELY 2 SECONDS), THRUST        ]
 ] DIRECTION ROTATES TO RCS SOLUTION CAUSING ADI ERROR NEEDLE PITCH    ]
 ] AXIS TO CHANGE AGAIN BUT HAS NO EFFECT IN YAW. FLIGHT SOFTWARE IS   ]
 ] PER REQUIREMENT.                                                    ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]_____________________________________________________________________]
 ]USER RESPONSE:                                                       ]
 ]                                                                     ]
 ] IGNORE SPIKE IN THE ADI ERROR NEEDLE PITCH AXIS DURING DOWNMODING   ]
 ] TO RCS.                                                             ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]                                                                     ]
 ]_____________________________________________________________________]
 ]CONCURRENCE:                           ]APPROVAL:                    ]
 ]IBM: WYATT COOPER         DATE 9/07/88 ]                             ]
 ]    --------------------      ---------]                             ]
 ]SSD: SAM ANKNEY           DATE 8/10/88 ]                             ]
 ]    --------------------      ---------] JACK G BOYKIN       9/20/88 ]
 ]PF MGR: ARTHUR HIEMER     DATE 7/29/88 ]------------------- -------- ]
 ]       -----------------      ---------] CHAIRMAN, SASCB      DATE   ]
 ]_______________________________________]_____________________________]
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