A330
Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Less Severe; Inflight Event / Encounter Other / Unknown
Flight Crew Diverted; Flight Crew Landed As Precaution; General Maintenance Action
Aircraft
During climb and cruise we had what we thought was continuous light chop. The chop did not subside and it seemed to us that the aircraft's pulsating/bumping movement was too rhythmic; too steady to be turbulence. We had flown the aircraft 3 legs already with no anomalies. My first concern was the rudder as the movement had a fishtail quality to it. ECAM F/CTL (flight control) page indicated ops normal on the rudder. However; the Captain noticed that the indicator (carrot) on the left outboard aileron was moving up and down rhythmically over a short range. The other seven aileron actuator indicators were near motionless. Flight control computers appeared normal; as did Yellow and Green hydraulics that powered the aileron.Convinced that we had a bad left outboard actuator we opted to [advise ATC] and land before the unit degraded further. The pulsing stopped upon flap extension during approach and landing and taxi was uneventful.
A330 First Officer reported the flight crew chose to divert to an alternate airport after noticing abnormal uncommanded aileron movement.