What was found
AIRCRAFT WAS GROUNDED: AT 16,000 FT 280 KNOTS ENGAGED AUTOPILOT YOKE MOVED BACK CAUSING MOMENTARY PITCH UP , THEN MOVED FORWARD NOTICEABLE VIBRATION AFTER LEVEL OFF. ACCOMPLISHED AMM 22-11-26-710-801 AUTOPILOT ACTUATOR TEST FAILED. AIRCRAFT DID NOT DECLARE AN EMERGENCY BUT RETURNED TO CLT. PERFORMED AUTOPILOT ELEVATOR ADJUSTMENT AND TEST PER AMM 22-11-26-820-810. OPERATIONS TEST SATISFACTORY.