Some Design Considerations on Powered Flying Controls

Powered flying‐control systems are a comparatively recent addition to aircraft and, to date, have been devised to modify as little as possible existing piloting technique. At the present time there is a basic similarity in most of the designs being used, and it is the purpose of this paper to consider the reasons for this and to examine the suitability of these systems for such future requirements as can be foreseen. Little has been published about the difficulties encountered in the installation of such systems, particularly of relation to stability and reliability, but some account is given in the paper of experience with one typical system which has been used in a number of aeroplanes of widely differing types. Whilst the scope of this paper is not intended to cover a detailed comparison of the minor features of various designs, some reference is made to those details which have a prime influence on performance. Finally, consideration is given to the extremely important question of pre‐flight rig testing, which is necessary to secure adequate reliability in services so vital to the safety of the whole aeroplane and its occupants.