As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF, AIR CONDITIONING PACKS PRODUCED A BLUE CLOUD OF BILLOWING SMOKE. FLIGHT RETURNED TO DTW AND LANDED WITHOUT INCIDENT. FOUND NR 2 AND NR 3 COALESCER BAGS DIRTY. REPLACED COALESCER BAGS AND PERFORMED PACK BURNOUT PROCEDURE. REPLACED AIR CYCLE MACHINE. OPERATIONAL CHECK NORMAL.