Q400
Flight Crew Air Transport Pilot (ATP)
Deviation / Discrepancy - Procedural Maintenance; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Flight Crew Returned To Departure Airport; Flight Crew Landed As Precaution; Flight Crew Landed in Emergency Condition; General Maintenance Action
Aircraft
Smoke in aircraft. Lav detector activiated and shortly thereafter smoke was observed and smelt. Returned to [departure airport]. Made visual app and landed; cleared runway in front of the gate area so rolled across taxiway and parked in gate area; then evacuated passengers out main cabin door.Aircraft may have been over serviced with oil.
The mechanics told me that the source of all the smoke was that the aircraft oil had been over serviced the night before.
Q400 flight crew reported returning to departure airport and evacuating the aircraft after experiencing smoke in the cabin. They were advised after landing the smoke was probably due to over-servicing the oil.