What was found
PHL - FL11, ON ARRIVAL IN PHL, THE LEFT FORWARD DOOR WAS OPEN WITH THE ESCAPE SLIDE STILL IN THE ARMED POSITION. THE SLIDE DID NOT DEPLOY. MAINTENANCE REPLACED THE SLIDE. AN EVALUATION BY THE SLIDE SHOP AND ENGINEERING COULD NOT DETERMINE THE CAUSE FOR THE NON-DEPLOYMENT OF THE SLIDE. PER COMPANY PROCEDURE, TWO MORE SLIDES WERE SCHEDULED FOR A DEPLOYMENT CHECK. (M)