What was found
JUST AFTER SELECTING SLATS EXTEND, RT HYD QTY FOLLOWED BY PRESSURE FELL TO ZERO. FOLLOWED QRH PROCEDURE AND LANDED STOPPING ON RUNWAY UNTIL MAINTENANCE CAME OUT TO SECURE DOORS. TOWED TO GATE. TSHOOT, FOUND RT SYSTEM PRESS FILTER HOUSING IN AFT AIRSTAIRS MISSING DELTA P INDICATOR ASSEMBLY. REMOVED AND REPLACED RT SYSTEM PRESSURE FILTER HOUSING. REMOVED AND REPLACED RT CASE DRAIN FILTER ELEMENT SERVICED RT HYDRAULIC SYSTEM. OPS AND LEAK CHECK BOTH FILTERS. NO DEFECTS NOTED. A/C OK FOR SERVICE. (M)