As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ORD - FLT 2039 - EN ROUTE PHL-ORD, SHORTLY AFTER TAKEOFF, DETECTED STRONG MUST ODOR AT CABIN AND COCKPIT. DISSIPATED AFTER GETTING AIRBORNE. LANDED ORD WITHOUT FURTHER INCIDENT. REPLACED COALESCER BAGS AND CLEANED WATER SEPARATORS. RAN BOTH PACKS. NO SMELL NOTED. SYSTEM GROUND CHECKED NORMAL OPS. (M)