Simulator Evaluation of a Medium-Cost Variable Stability System for a Business Jet

This paper discusses an approach to convert the longitudinal dynamics of the Cessna Citation into a variable stability platform using response feedback, thereby enabling it to take different positions on the Control Anticipation Parameter (CAP) handling quality criterion. The different positions of an aircraft on the criterion reflect different handling qualities, short period damping ratios and CAP. An experiment is performed to investigate whether the handling qualities found analytically, as a result of a variable stability control law, match those found practically from pilot tests on an aircraft simulator. Results of the experiment show that pilots are able to sensitive to even small changes in aircraft dynamics caused by the variable stability system, however, their judgment of the handling qualities does not always agree with handling qualities predicted analytically from the CAP criterion.