What was found
FLT MAC 111 - OMFJ-LICZ - AIRCRAFT EXPERIENCED RAPID DE-PRESSURIZATION AT FL 390. CABIN ALTITUDE STABILIZED AT 13,500 FEET. MAX CABIN DIFFERENTIAL AT 6.6 PSI. PERFORMED CHECKLIST IAW QRH. MAINTENANCE FOUND THE FORWARD AIR CONDITIONING ACCESS DOOR OUT OF ADJUSTMENT. MAINTENANCE ADJUSTED THE ACCESS DOOR IAW EWA MM. GROUND PRESSURIZATION WAS GOOD. NO PRESSURIZATION DISCREPANCIES WERE REPORTED ON SUBSEQUENT FLIGHTS AS OF 10/24.