The patent application relates to a system for rapidly disengaging, with minimum nuisance disengagements, a conventional autopilot system upon detecting hardover failure, which is defined as any autopilot failure which results in rapid and sustained displacement of an aircraft aerodynamic control surface. The aircraft pitch rate is measured and compared with established limits. If these limits are exceeded, the system causes automatic disengagement. Disengagement is inhibited for gust disturbances by deriving a nose up or down signal from the pitch rate signal which is then compared with a signal indicating the direction of elevator hinge moment; if the two directions are opposing, disengagement is inhibited. Disengagement is also inhibited in the event of pilot action. Also, the autopilot pitch axis command line is monitored and a disengagement overriding any inhibits is generated when the signal on that line exceeds certain limits for the altitude hold mode and for the attitude hold mode of the autopilot.


    Access

    Access via TIB

    Check availability in my library


    Export, share and cite



    Title :

    Autopilot Hardover Failure Protection System


    Contributors:

    Publication date :

    1976


    Size :

    28 pages


    Type of media :

    Report


    Type of material :

    No indication


    Language :

    English




    Autopilot Hardover Failure Protection System

    S. T. Donley / V. A. Freitag | NTIS | 1976



    Autopilot system

    ALBION NICOLAS / BARTEL MARK / FEIFEL MARC et al. | European Patent Office | 2020

    Free access

    Aircraft flight envelope protection and recovery autopilot

    PROSSER KEVIN | European Patent Office | 2023

    Free access

    Aircraft flight envelope protection and recovery autopilot

    PROSSER KEVIN | European Patent Office | 2019

    Free access