Design and Analysis of a Blended Command Model for Low Speed Flight

To achieve Level 1 Handling Qualities, Aeronautical Design Standard ADS-33E-PRF requires an Attitude Command Attitude Hold or Translational Rate Command response-type in Degraded Visual Environments while allowing a rate response in Good Visual Environments. The authors describe the design and analysis of a Blended Command Model that may offer the precision of the former and the aggressiveness of the latter. The command model, comprised of a single flexible transfer function and its parameter scheduling functions, produces attitude, rate, and blended responsetypes as functions of cyclic stick position. The authors explain the command model’s design considerations, test considerations, and its behavior through time domain and frequency domain perspectives. This effort precedes a handling qualities assessment aboard the U.S. Army’s JUH-60A RASCAL aircraft.