Narrative:

I was returning from my scheduled break when I was asked by the flying pilots to go to the back of the aircraft and observe if the aircraft was doing anything abnormal. I walked back to the aft galley and noticed that the aircraft was oscillating pitch up and down while in smooth air conditions. I returned to the flight deck and observed the right side elevator indicator on the status page oscillating at the same rate that was consistent with what I was feeling in the back of the aircraft. I relieved the captain from her seat and had her go back to observe the uncommanded pitch movements. Upon her return; we discussed our options with maintenance control and dispatch; and decided that this was a safety of flight concern rendering the aircraft unsafe to continue flight operations. We ran all appropriate checklist items; and diverted to ZZZZ. During the approach; elevator oscillations were noted all the way down the ILS; with the autopilot coupled and also when the aircraft was being manually flown by the crew. After an uneventful and successful landing at the airport; the first officer and myself did a post flight walk around and noticed that the right side elevator was completely drooped down while the left side was only partially drooped.

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Original NASA ASRS Text

Title: A Captain and First Officer describe the pitch oscillations their B767-300 aircraft experienced in smooth air about two hours after departure. The right elevator indicator on the EICAS status page was oscillating at the same rate that was consistent with what was felt in the back of the aircraft. The oscillations were more noticeable as the aircraft slowed and continued all the way to a diverted landing. Aircraft was ferried to a maintenance base.

Narrative: I was returning from my scheduled break when I was asked by the flying pilots to go to the back of the aircraft and observe if the aircraft was doing anything abnormal. I walked back to the aft galley and noticed that the aircraft was oscillating pitch up and down while in smooth air conditions. I returned to the flight deck and observed the right side elevator indicator on the status page oscillating at the same rate that was consistent with what I was feeling in the back of the aircraft. I relieved the Captain from her seat and had her go back to observe the uncommanded pitch movements. Upon her return; we discussed our options with Maintenance Control and Dispatch; and decided that this was a safety of flight concern rendering the aircraft unsafe to continue flight operations. We ran all appropriate checklist items; and diverted to ZZZZ. During the approach; elevator oscillations were noted all the way down the ILS; with the autopilot coupled and also when the aircraft was being manually flown by the crew. After an uneventful and successful landing at the airport; the First Officer and myself did a post flight walk around and noticed that the right side elevator was completely drooped down while the left side was only partially drooped.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.