What was found
PRONOUNCED AIRFRAME VIBRATION AFTER GEAR & FLAP RETRACTION. NOTICEABLE VIBRATION IN YOKE & ON FLOOR. FELT SPOILERS WEAR PARTLY UP. ENG INDICATIONS NORMAL. TROUBLE SHOT AIRFRAME VIBRATION IAW AMM 05-51-67. NO DEFECTS NOTED ON GND. THIS SUBMISSION FOR MRR PURPOSES & CONSIDERATION. ACFT ENROUTE BUT RETURNED FOLLOWING ABOVE FLIGHT DISCREPANCY. ACFT HAD DEPARTED FOLLOWING KA, SSW MOD VISIT. FOLLOWING EG & TOMC TROUBLESHOOTING DIRECTIONS THERE WERE NO DEFECTS FOUND. ACFT SUBSEQUENTLY FLEW WITH A CHECK CREW WITH NO ABNORMAL VIBRATION NOTED & RETURNED TO SERVICE.