As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING T/O CLIMBOUT, CREW DETECTED AN ODOR THAT RESEMBLED BURNING PLASTIC. ODOR CONTINUED TO GET WORSE AS CREW EXECUTED IMMEDIATE RETURN TO DEPARTURE. ODOR STOPPED AFTER LANDING. REMOVED AND REPLACED LT AND RT OZONE CONVERTERS IAW MM 21-71-00. OPS AND LEAK CHECK GOOD. NO ODORS NOTED.