As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON FLIGHT 4053 THE FLIGHT ATTENDANT REPORTED AFTER TAKEOFF DETECTED AN ODOR OF BURNING RUBBER WHICH WENT AWAY BUT DURING LANDING THE ODOR CAME BACK. ON THE POST FLIGHT NOTICED ODOR COMING FROM THE NR 1 PACK. THE AIRCRAFT WAS REMOVED FROM SERVICE. REMOVED AND REPLACED THE DUAL HEAT EXCHANGER NR 1 IAW AMM 25-51-02. THE OPERATIONAL CHECK WAS GOOD. THE AIRCRAFT WAS RETURNED TO SERVICE.