Actuator and Hydraulic Survivability Concepts for Hughes YAH-64

This presentation will provide an overview of the hydraulic and flight control system, indicating the functions of the hydraulic systems, and the various components incorporated in the flight control actuators used on the Hughes YAH-64. A brief review of the design philosophy used in arriving at the system as implemented is included. The system concepts, which were incorporated in the flight control hardware to survive malfunctions or battle damage, will be particularly emphasized. The specific implementation of the automatic, hydro-mechanical isolation, incorporated to tolerate damage or failure to non-critical flight components, and the isolation system, incorporated to tolerate the hydraulic power generation system failure, are described in detail. The system concepts incorporated in the flight control hardware to survive battle damage or system malfunctions are discussed. This includes the direct manual flight control mechanism; the stability augmentation system; and the backup control, fly-by-wire system. The specific hardware design, incorporated in the flight control actuators to render them ballistic tolerant, is discussed in detail as well as the significance of the designated threat. Alternate hardware configurations which were developed and tested for the Sikorsky Black Hawk actuators to survive similar threats are discussed. A summary of the various configurations which were tested and the results of ballistic tests on development hardware configurations are presented.