A generic control anticipation parameter for aircraft handling qualities evaluation

Abstract

The established control anticipation parameter longitudinal handling qualities criterion is based on the assumption that the short term dynamic response of the aeroplane is classical, or second-order-like. Modern fly-by-wire aircraft often have longitudinal short term dynamics which are not second-order-like and to which it is difficult to apply the criterion. This paper presents a proposed generic control anticipation parameter which is a modified version of the control anticipation parameter and which may be applicable to both unaugmented and augmented aircraft of all types. The appropriateness of the modified criterion was illustrated by designing a number of command and stability augmentation control laws, constrained to meet the criterion, for application to a medium weight fly-by-wire civil transport aircraft. The handling characteristics conferred by the control laws were assessed in a series of flight simulator trials, the results of which are briefly presented.

On the Handling Qualities of Two Flying Wing Aircraft Configurations

“…The general theory with strong coupling was developed in the expectation of longitudinal-lateral coupling that may occur is some flight conditions, like high angle-of-attack close to stall. In the present cases of flight at moderate anglesof-attack far from stall, the weak coupling version of the general theory is still useful to confirm that the small terms in the coupling matrices do not affect to a significant extent the frequencies and dampings, allowing the application of the decoupled HQs criteria, for which there exists substantial literature [64][65][66][67][68][69][70][71][72][73][74][75][76][77][78][79][80].…”

“…There are more refined versions of the CAP HQs criterions [77], often used in modern literature on aircraft HQs [78][79][80][81][82][83][84][85]. The usual approaches CAP need not to be refined further here, because it is related [73,76] to the manouever margin, considered in more detailed in Section 3.3.…”