What was found
STRONG VIBRATIONS FELT FROM NOSE TO TAIL AT CRUISE AT .79M OTHER ABNORMALITY FELT DURING LANDING PHASE WITH AUTOPILT ENGAGED, MINOR LT & RT MOVEMENT FELT. WITH AUTOPILOT DISCONNECTED, MOVEMENT STOPPED. CREW REPORTED AIRFRAME VIBRATION STARTED AFTER DECENDING FROM 30,000 - 26,000 FT IN CRUISE . F/AS ALSO CONFIRMED AIRFRAME VIBRATION FELT THROUGHOUT CABIN. AFTER SLOWING DOWN TO 250 KNOTS, VIBRATION STOPPED. REMOVED GREEN SERVO CONTROL ACTUATOR IAW AMM 27-34-51. INSTALLED ELEVATOR SERVO CONTROL IN REF TO AMM 27-34-51-400-001-A. OPS CHECKS GOOD IN REF TO AMM 27-34-00-820-001-A, 27-34-00-710-001-A.