Narrative:

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 crash fire rescue equipment 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.

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Original NASA ASRS Text

Title: CRJ-900 flight crew reported returning to their departure airport after receiving an EICAS message 'SMOKE AFT LAV' and smelling fumes in the cabin.

Narrative: 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.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.