Recent NOTAR® Anti-Torque System Research and Testing at MDHC

The anti-torque system of a helicopter has a major impact on the weight, performance, agility, reliability flight and ground crew safety, and vehicle survivability. McDonnell Douglas Helicopter Company (MDHC) has been working on the No-Tail Rotor (NOTAR®) concept for the past seventeen years. It has only been in the last few years that the development of the system into a production anti-torque system has taken place. NOTAR anti-torque system research and development at MDHC have emphasized a structured approach. First, the performance of the individual NOTAR system components were measured and evaluated in experiments at MDHC. Then, integrated system performance was investigated in ground testing, powered model rotor wind tunnel testing, and flight testing of three different aircraft with the NOTAR system - OH-6 Demonstrator, MD 520N/530N and MD 900. This paper describes recent component and system testing that has led to production versions of the NOTAR anti-torque system.