What was found
DFW - FLT 1718 - AFTER TAKEOFF DFW DURING CLIMB-OUT, SLIGHT SMOKE NOTED IN CABIN AND COCKPIT. AIRCRAFT RETURNED TO DFW AND LANDED OVERWEIGHT WITHOUT INCIDENT. ACCOMPLISHED PACK BURNOUT PROCEDURE. ACCOMPLISHED OVERWEIGHT LANDING INSPECTION WITH NO DEFECTS FOUND. ACCOMPLISHED FUNCTIONAL CHECK FLIGHT AND PROBLEM REPEATED. REPLACED APU. ACCOMPLISHED PACK BURNOUT PROCEDURE AND REPLACED ALL COALESCER BAGS. SYSTEM GROUND CHECKED NORMAL OPERATION. ACCOMPLISHED FUNCTIONAL CHECK FLIGHT WITH NO DEFECTS FOUND. SYSTEM OPERATIONAL CHECKED NORMAL. (M)