 +_____________________________________________________________________
 ] AUTHOR:            ]                             ] DR:              ]
 ] CRAWFORD FLETCHER  ]    PASS PROGRAM NOTE        ]       46501      ]
 ]____________________]                             ]__________________]
 ] ORG/PHONE:         ] OPS NOTE ( )  USER NOTE (X) ] DATE: SEPT. 1987 ]
 ] LSIS/282-7333      ]      RELEASE NOTE( )        ] REV B: 10/26/94  ]
 ]____________________]_____________________________]__________________]
 ] OI/FLIGHT EFFECTIVITY:        ]  USER AFFECTED:                     ]
 ] REL 19 AND SUBS               ]  CREW ( )  GROUND (X)  DUMP ONLY ( )]
 ]_______________________________]_____________________________________]
 ]        MAJOR SOFTWARE AREA:       ] OPS MODES AFFECTED:             ]
 ]SSW ( )  GNC (X)  VU ( )  SM/PL ( )] G3, G6                          ]
 ]_____________________________________________________________________]
 ] SOFTWARE SUB-AREA: GPC                                              ]
 ]_____________________________________________________________________]
 ] PRINCIPAL FUNCTIONS: 4.23, 4.24, 4.25, 4.20                         ]
 ]_____________________________________________________________________]
 ] TITLE:                                                              ]
 ] POTENTIAL GPC ERRORS DURING BRAKING AND AFTER ROLLOUT ON THE RUNWAY ]
 ]_____________________________________________________________________]
 ] DESCRIPTION:                                                        ]
 ]                                                                     ]
 ] USER PARAMETER PROCESSING REQUIREMENTS FOR THE COMPUTATION OF       ]
 ] ALTITUDE RATE (H) IN MM 305 AND MM 603 INCLUDE A COMPENSATION FOR   ]
 ] PITCH RATE EFFECTS.  THIS COMPENSATION SUBTRACTS THE "FALSE"        ]
 ] COMPONENT OF ALTITUDE RATE SENSED BY THE IMUS WHEN THE VEHICLE IS   ]
 ] EXPERIENCING PITCH RATES.                                           ]
 ]                                                                     ]
 ] AS THE VEHICLE IS STOPPING ON THE RUNWAY, THE VELOCITY IS NEARLY    ]
 ] ZERO.  VEHICLE ROTATIONS SUCH AS THE 'ROCK-BACK' EFFECT AFTER       ]
 ] BRAKING OR NOISE IN THE SELECTED RGA PITCH RATE MAY PRODUCE         ]
 ] ERRONEOUS ALTITUDE RATES DUE TO THE ACTUAL NUMERIC VALUES USED.     ]
 ] IF A  SMALL ALTITUDE RATE RESIDUAL VALUE EXISTS AFTER THIS PITCH    ]
 ] RATE COMPENSATION HAS BEEN APPLIED, A NEGATIVE SQUARE ROOT ARGUMENT ]
 ] GPC ERROR MAY BE OBSERVED. THIS SQUARE ROOT OCCURS IN THE           ]
 ] GROUNDSPEED CALCULATION.  IN AN RTLS CASE, A GPC ERROR MAY ALSO BE  ]
 ] OBSERVED FOR THE ABSOLUTE VALUE OF AN ARCSIN ARGUMENT GREATER THAN  ]
 ] ONE.  THIS ARCSIN OCCURS IN THE FLT_PATH_ANG CALCULATION.  THESE    ]
 ] GPC ERRORS MAY ALSO BE OBSERVED AS THE VEHICLE IS STATIC ON THE     ]
 ] RUNWAY.                                                             ]
 ]_____________________________________________________________________]
 ]USER RESPONSE:                                                       ]
 ]                                                                     ]
 ] IGNORE GPC ERRORS EXPERIENCED DURING BRAKING OR AFTER ROLLOUT IF    ]
 ] ANALYSIS CONFIRMS THAT THE SOURCE IS A NEGATIVE SQUARE ROOT (ERROR  ]
 ] GROUP 4, CODE 5) AND/OR ARCSIN ARGUMENT OUT OF RANGE (ERROR GROUP 4,]
 ] CODE A) IN THE MID-FREQUENCY EXECUTIVE (GEQENT OR GEGASC).          ]
 ]_____________________________________________________________________]
 ]CONCURRENCE:                           ]APPROVAL:                    ]
 ]LSIS:   JEAN L. ZOPHY     DATE 12/20/94]                             ]
 ]     -------------------      ---------]                             ]
 ]ASD:   ERIC C. BINGHAM    DATE 12/20/94]                             ]
 ]     -------------------      ---------] DARRELL E. STAMPER 01/05/95 ]
 ]PF MGR:  M. N. MONTEZ     DATE 01/04/95]------------------- ---------]
 ]       -----------------      ---------] CHAIRMAN, SASCB      DATE   ]
 ]_______________________________________]_____________________________]
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