A transmission gearbox for a rotary-wing aircraft includes a main gearbox and a variable speed gearbox in meshing engagement with the main rotor gearbox. The variable speed gearbox permits at least two different RPMs for the main rotor system without disengaging the engine(s) or changing engine RPMs. The variable speed gearbox includes a clutch, preferably a multi-plate clutch, and a freewheel unit for each engine. A gear path drives the main gearbox in a “high rotor speed mode” when the clutch is engaged to drive the main rotor system at high rotor rpm for hover flight profile. A reduced gear path drives the main gearbox in a “low rotor speed mode” when the clutch is disengaged and power is transferred through the freewheel unit, to drive the main rotor system at lower rotor rpm for high speed flight. The variable speed gearbox may be configured for a tail drive system that operates at a continuous speed, a tail drive system that changes speed with the main rotor shaft or for no tail drive system.


    Access

    Download


    Export, share and cite



    Title :

    VARIABLE SPEED TRANSMISSION FOR A ROTARY WING AIRCRAFT


    Additional title:

    ANTRIEB MIT VERSTELLBARER DREHZAHL FÜR EIN DREHFLÜGELFLUGZEUG
    TRANSMISSION À VITESSE VARIABLE POUR AÉRONEF À VOILURE TOURNANTE


    Contributors:

    Publication date :

    2017-01-11


    Type of media :

    Patent


    Type of material :

    Electronic Resource


    Language :

    English


    Classification :

    IPC:    B64C AEROPLANES , Flugzeuge



    High speed compound rotary wing aircraft

    SCOTT MARK W / GATTO STEPHEN M | European Patent Office | 2015

    Free access

    HEAVY HIGH-SPEED ROTARY-WING AIRCRAFT

    DUROV DMITRIJ SERGEEVICH | European Patent Office | 2017

    Free access


    Rotary wing of fixed-wing aircraft and aircraft with rotary wing

    CHEN MINGJUN / HE LIJUN / PENG JIANPING et al. | European Patent Office | 2024

    Free access

    Rotary wing aircraft bearing for rotary wing aircraft motions

    HALLADAY JAMES R / SHERIDAN PATRICK M / DOWNING MARSHALL W et al. | European Patent Office | 2020

    Free access