The S-92 Goes Fly By Wire…

The fixed wing community has been manufacturing civil fly by wire aircraft for decades, but until now helicopter manufacturers had yet to join the trend. Sikorsky Aircraft recently embarked on a program to develop the first FAA-certified helicopter fly by wire system — a modified version of the S-92A designated the S-92F. This paper highlights some key differences of the S-92F. High levels of redundancy comply not only with FAA mandates, but assure enhanced mission reliability. The S-92F incorporates small displacement unique trim cyclic controller and yaw controls, and a conventional displacement collective control. The physical characteristics of this innovative configuration are discussed. The full authority, high rate, augmentation offered by the fly by wire system greatly enhances the pilot’s ability to precisely control and maintain aircraft flight path thereby reducing pilot workload. Combinations of automatic and pilot selectable modes are available. Challenges in implementing and certifying the fly by wire system are reviewed.