What was found
FLT#348, LAS-JFK. 'DESCENDING INTO JFK ENTERED CLOUDS AT 10,000 AND HAD DIRTY SOCK SMELL UNTIL EXITING CLOUDS AT 4,000, SMELL IN COCKPIT AND FWD AND AFT CABIN, FUMES/ODOR FOR COMPLETED; PERFORMED INDO NOTICE 2017-T015K, IDENTIFIED ODOR AS TYPE 1. APU FOUND TO BE SOURCE OF ODOR, LEAKING FROM MIDDLE DRAIN MAST. APU PLACED ON MEL, REF ITEM #2, DECON LEVEL A WAS ACCOMPLISHED PER TSM 05-50-00-810-085. A/C OK FOR SVC.'