What was found
AIRCRAFT RETURNED OF FLIGHT, MAIN LANDING GEAR UNLOCK INDICATION AND STRONG VIBRATION. DURING MAINTENANCE REVISION, RT AND LT LOCK PINS WERE DETECTED INSTALLED IN MAIN LANDING GEAR. LOCK PINS WERE REMOVED AND MAIN LANDING GEAR AND OVERWEIGHT INSPECTION WERE PERFORMED IAW MM 32-30-00 AND 05-51-04, RESPECTIVELY, ALL CORRECT.