As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 5891 - YOW-PHL - RETURNED TO FIELD AFTER PACKS OVERHEATED AND THERE WAS SMOKE IN THE COCKPIT. MAINTENANCE INSPECTED THE PACKS, INCLUDING OILS, AND RAN THE ENGINES. NO SMOKE OR DEFECTS NOTED. THE AIRCRAFT WAS RETURNED TO SERVICE. (M)