What was found
ON POST FLIGHT WALKAROUND, LOUD HISSING WAS HEARD INBOARD OF NR 4 ENGINE AND WING L/E EDGE BULLNOSE ADJACENT TO NR 19 VARIABLE CAMBER L/E FLAP WAS DENTED TOP AND BOTTOM. RIGHT WING PNEUMATICALLY ISOLATED AND HISSING STOPPED. CLOSE INSPECTION REVEALED RIGHT WING THERMAL DEICE S/O VALVE STUCK IN THE MID POSITION AND THE WING WAS TOO HOT TO TOUCH. REPLACED RIGHT L/E THERMAL DEICE VALVE IAW MM 30-11-03. C/W SPECIAL INSPECTIONS 5-51-18 PRESSURE DEICING DUCT FAILURE, 5-51-30 HOT AIR DUCT INSPECTION, 05-51-71 GROUND HANDLING EQUIP HITS AIRCRAFT, 5-51-14 BIRD/HAIL STRIKE CONDITION, AND 05-51-03 SEVERE TURBULANCE CONDITIONAL INSPECTION. REPAIRED RT WING LEADING EDGE AT WS 889.5 AND WBL 692 IAW SRM 57-20-03 FIG 7, UPPER CHORD AND WEB IAW SRM 57-20-03 FIG 7 AND LOWER CHORD IAW SRM 51-40-04 FIG 2.