As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DFW - FLT 1684 - DURING TAKEOFF, CREW NOTICED SEWAGE SMELL FOLLOWED BY A BURNING SMELL. FLIGHT AIR INTERRUPTED AND RETURNED DFW AND LANDED OVERWEIGHT WITHOUT INCIDENT. ACCOMPLISHED OVERWEIGHT INSPECTION WITH NO DAMAGE NOTED. PACKS INSPECTED FOR POSSIBLE INGESTION WITH NO INGESTION NOTED. GROUND RAN ENGINES AT POWER UTILIZING BLEED AIR FOR PACK, UNABLE TO DUPLICATE ORDER. SYSTEM GROUND CHECKED NORMAL OPERATION. (M)