As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED A "BURNING DUST" ODOR DURING TAKEOFF THAT DISSIPATED WHEN THE CABIN HEAT WAS TURNED DOWN. AFTER TAKEOFF, CREW OBSERVED A STRONG MELTING PLASTIC ODOR IN THE COCKPIT AND CABIN. THE CREW RETURNED TO FIELD AND DECLARED AN EMERGENCY. ACFT LANDED WITHOUT INCIDENT. THE GROUND MX CREW INSPECTED AND FOUND THE NR 2 ACM TO BE INOPERATIVE.