As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DFW - FLT 1935 - AFTER TAKEOFF DFW, CREW REPORTED STRONG ACRID SMELL AND SMOKE IN REAR OF CABIN. AIRCRAFT RETURNED TO DFW AND LANDED OVERWEIGHT WITHOUT INCIDENT. REPLACED RIGHT HAND AIR CYCLE MACHINE AND BOTH COALESCER BAGS. ACCOMPLISHED OVERWEIGHT LANDING INSPECTION WITH NO DEFECTS FOUND. PERFORMED PACK BURN-OUT PROCEDURE. SYSTEM GROUND CHECKED, NORMAL OPERATION. (X)