What was found
WITH AUTOPILOT DISENGAGED AT CRUISE FLT, UNCOMMANDED FWD/AFT MOVEMENT OF CONTROL WHEEL HAD TO BE COUNTER-ACTED WITH FIRM PRESSURE. UNCOMMANED MOVEMENT OF CONTROL WHEEL SEEMED TO LESSEN WITH SLOWER AIRSPEED (310-200 KIAS). THIS PROBLEM WAS DISCOVERED AFTER DISENGAGING A/P BECAUSE OF ACCOMPANYING WRITE UP. WITH -A- AND B-HYD SYSTEMS PRESSURIZED, A/P OFF AND C/B'S PULLED, FOUND RT ELEVATOR TRIM TAB WOULD DEFLECT INTERMITTENTLY. REMOVED LARGE COMPACTED BIRD NEST FROM RT ELEVATOR POWER PACKAGE BAY AND BLED B-SYSTEM WITH BLEED NEXT TO B-MODULAR PACKAGE IN AFT STAIR WELL. RT TRIM TAB NOW IS STEADY. CHECKED ELEVATOR TRIM TABS AND ELEVATORS FOR BINDING. OPS CHECKS GOOD PER MM 27-30-000-5.