What was found
MCI - FLT 350 - DURING FLIGHT AT 300 KNOTS, AIRCRAFT HAD LOW FREQUENCY AIRFRAME VIBRATION. PERFORMED DETAILED INSPECTION OF FLIGHT CONTROLS IAW BOEING MM 27-11-00, 27-51-0 AND 27-61-0, NO DEFECTS FOUND. INSPECTED AIRCRAFT A/C BAY DOORS IAW BOEING MM 52-49-0, NO DEFECTS FOUND. INSPECTED THE MAIN LANDING GEAR DOORS AND FOUND THE RIGHT OUTER DOOR WITH LOOSE BUSHINGS AND HARDWARE. REMOVED DOOR AND PLACED ON CDL ITEM NR C912410. (M)