Redundant helicopter pitch change bearing

An aircraft rotor assembly, comprising:

• a rotating pitch change shaft which rotates about an axis;
• a translating element disposed within the rotating pitch change shaft and movable along the axis;
• and
• a pitch change bearing assembly which transfers movement of the translating element to the pitch change shaft, the assembly including:
• a primary bearing coupled to the rotating pitch change shaft via the translating element when the primary bearing is in a first mode;
• a secondary bearing coupled to the rotating pitch change shaft via the translating element when the primary bearing is in a first mode;
• and
• a thrust shoulder coupled to the translating element, the thrust shoulder being movable into engagement with the secondary bearing in response to failure of the primary bearing in the first mode and such that, in a second mode, movement of the translating element is primarily transferred to the pitch change shaft via the secondary bearing.