A force feel system for an aircraft having a control member or stick connected to a boost actuator for positioning an aircraft control surface and a variable force gradient spring mechanism for providing a feedback of artificial forces to the control stick, and which includes non-linear or irreversible linkage apparatus coupled between the stick and the variable force gradient spring such that the force feel system does not require the implementation of monitoring or redundant systems to provide fail safe operation in the event of failure of said force feel system. In addition, the "hands off" stability of the aircraft is not affected by the system because in this "hands off" mode of operation the non-linear linkage apparatus prevents the force actuator from moving the control stick out of the trim position.
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