Regional Jet 200 ER/LR (CRJ200)
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Air Traffic Control Provided Assistance; Flight Crew Landed in Emergency Condition; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Returned To Departure Airport; General Maintenance Action
Aircraft; Human Factors
After takeoff from Runway 24R; while retracting the flaps we received a SMOKE TOILET caution message and smoke detector audible alarm. We did smell smoke and the cabin appeared hazy. We decided to return to ZZZ. I ran the QRH while the Pilot Flying flew the aircraft. Approach had us on a right downwind to Runway 18 and cleared us to land; relayed to us from the Tower through ZZZ approach. [ATC was advised] and trucks rolled. While on downwind the smoke began to dissipate and the audible alarm stopped. We landed and after the fire trucks told us they did not see any external indication of smoke or fire we taxied to the hangar. Trucks followed us to parking. Cause: Maintenance found that the Right Hand engine had been over serviced with oil.Suggestions: This aircraft had sat for several weeks awaiting end of lease work and processes. Although Maintenance took precautions and ran the aircraft the day before; they did not run the packs on the engine bleeds. Risk is increased occurrences due to system failures when aircraft are return to service after being in storage. Mitigation is maintenance and crew awareness.
CRJ-200 Captain reported that a lavatory smoke warning and cabin fumes event resulted in a return to the departure airport.