What was found
AIRCRAFT WAS GROUNDED: STRONG ODOR LIKE CHEESE OR SMELLY FEET ALL THROUGHT CABIN IN CRUISE, SMELL DISSIPATE DESCENDING THROUGH 1700 FEET MSL, STRONG ODOR RETURNED AND THEN DISSIPATED AGAIN THROUGH 500 FT. **SUPPLEMENTAL REPORT FOR AALA202401032269: MAINTENANCE NOTED THE APU COMPARTMENT WAS SOAKED IN OIL WHEN IT WAS OPENED. MAINTENANCE ACCOMPLISHED A CLEANING OF THE COMPARTMENT AND RAN THE APU FOR SEVERAL HOURS WITH NO LEAKS NOTED. MAINTENANCE ACCOMPLISHED THE DECONTAMINATION OF THE ENVIRONMENTAL CONTROL SYSTEM ALONG WITH A OPERATIONAL CHECK WITH NO LEAKS OR ODORS NOTED.** (CLOSED)