As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FUME EVENT DESCENDING THRU 17,000 - 18,000 DIRTY SOCK SMELL DETECTED THEN DISAPPEARED. RETURNED AT 10,560 FEET MUCH STRONGER DIRTY SOCK SMELL. CHECKLIST PROCEDURE CALLED FOR PACK 1 OFF. UNKNOWN IF ODOR PERSISTED DUE TO OXYGEN USE TO GATE. COMPLIED WITH W/O 603333 NR 1 ENGINE REMOVED AND REPLACED IAW TASK CARDS MP71042-05 AND MP71042-06. AC RETURNED TO SERVICE. ORIGINAL SUBMISSION DATE: 06/10/2026