What was found
DURING ROUTINE INSPECTION OF NR 2 RT THRUST REVERSER, MX FOUND THE THRUST REVERSER NOT STOWING. AFTER INSPECTION FOUND UPPER BALLSCREW ACTUATOR AT FAULT. PERFORMED A DETAIL INSPECTION OF THE REVERSER HALF IN QUESTION INCLUDING REVERSER CONE BRAKE FUNCTIONAL CHECK, IAW AMM 78-31-00. REMOVAL OF THE DEFECTIVE UPPER ANGLE GEARBOX BALLSCREW ACTUATOR JACKSCREW AND REPLACING IT WITH THE LOWER BALLSCREW ACTUATOR. LOWER ACTUATOR POSITION WILL NOT BE INSTALLED. PERFORMED DEACTIVATION OF THE NR 2 ENGINE THRUST REVERSER IAW DDG 78-31-1.