As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MIA - FLT 596 - AFTER TAKEOFF, WHOLE AIRPLANE HAD PLASTIC BURNING SMELL. RETURNED AND LANDED MIA WITHOUT INCIDENT. ACCOMPLISHED ENGINE RUN UP AT DIFFERENT POWER SETTINGS, ACCOMPLISHED PACK BURNOUT AND CHANGED COALESCER BAGS ON BOTH PACKS. NO ODOR NOTICED. SYSTEM GROUND CHECK NORMAL OPERATION. (M)