Review and investigation of unsatisfactory control characteristics involving instability of pilot-airplane combination and methods for predicting these difficulties from ground tests

William H. Phillips, B. Porter Brown, James T. Matthews, Jr
naca-tn-4064
Aug 1957


A number of examples are presented of control difficulties which appear to result from a tendency for dynamic instability of the combination of pilot, control system, and airplane. The unsatisfactory characteristics involved have been encountered most frequently with hydraulic-power control systems, although several cases have also been experienced with conventional control systems. Tests of a bomber and a fighter airplane with experimental power control systems have been made to study this problem further.

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