Control Law Design for Compliance with ADS-33C Failure State Requirements, the Comanche Approach

The RAH-66 Comanche flight control laws are assessed with respect to failure requirements imposed by the governing handling qualities specification, ADS-33C. This assessment is based on analysis and piloted simulation. The ADS-33C requirements for failure states are compared to prior guidance from the handling qualities Military Specification 8501A that it supersedes. The Boeing Sikorsky approach for Comanche compliance with ADS-33C, which is currently under Army review, is outlined. Presentation of failure scenarios is made with respect to the affected portion of the flight control system. A balanced demonstration of compliance using probability analyses and documentation of response to specific failures is advocated.