Regional Jet 900 (CRJ900)
Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Less Severe; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Air Traffic Control Issued New Clearance; Air Traffic Control Provided Assistance; Flight Crew Returned To Departure Airport; Flight Crew Landed As Precaution
Aircraft; Procedure
After takeoff and prior to acceleration altitude; the EICAS illuminated the SMOKE AFT LAV master warning message. The first officer was the pilot flying and also handled the radios while I contacted the flight attendants. I asked them if they smelled smoke or fumes in the cabin. I also asked them to check the aft lavatory waste basket for smoke or fire. The flight attendants said there was a strong smell of fumes in the cabin but there was no smoke or fire coming from the aft lavatory waste basket. However; she said the passengers were complaining of strong fumes in the cabin. I [advised ATC] and asked for CFR services to meet the airplane upon landing. All company procedure were followed and we returned to land. I asked the fire marshal to board the aircraft and evaluate the cabin. He agreed to inspect the cabin and pronounced the situation all clear. I contacted dispatch and taxied to the gate where the passengers were deplaned. I then contacted maintenance with a log book entry.
[Maintenance] diagnosed the problem to be from an improperly performed engine maintenance the night prior.
CRJ-900 flight crew reported returning to their departure airport after receiving an EICAS message 'SMOKE AFT LAV' and smelling fumes in the cabin.