Narrative:

Shortly after take-off (approximately 200 ft AGL) the flight attendant called the cockpit using the interphone system. She reported smoke in the cabin. The EICAS then presented lav smoke (approximately 400 ft AGL) and the 3 chime warning system sounded. I requested that the captain contact ATC and request an immediate return for landing. Tower cleared us to turn left and maintain 3;000 ft; and then cleared us to land on the runway. We configured for landing and landed safely on the runway. The aircraft was under max landing weight. We exited at the end of the runway and stopped clear of the runway. We queried the flight attendant via interphone to assess the situation in the cabin to decide if it was safe to return to the gate or deplane immediately. She informed us that there was not a fire in the cabin. We asked the emergency fire response unit to assess our condition from the outside. Concluding that it was safe to return to the gate; we ran any appropriate checklists; contacted company to receive a gate assignment; and clearance from ATC to taxi back to the ramp. The passengers were deplaned; the fire unit came aboard to inspect for fire damage. During this time there was still a haze of smoke in the cabin. Maintenance came aboard; the captain wrote up the discrepancy. Maintenance and the captain discussed the event and the aircraft was left with maintenance.

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Original NASA ASRS Text

Title: An EMB140 Flight Attendant notified the pilots of smoke in the cabin immediately after takeoff while the lavatory smoke warning was alerting. An emergency was declared and the aircraft returned to land at the departure airport.

Narrative: Shortly after take-off (approximately 200 FT AGL) the Flight Attendant called the cockpit using the interphone system. She reported smoke in the cabin. The EICAS then presented LAV SMOKE (approximately 400 FT AGL) and the 3 chime warning system sounded. I requested that the Captain contact ATC and request an immediate return for landing. Tower cleared us to turn left and maintain 3;000 FT; and then cleared us to land on the runway. We configured for landing and landed safely on the runway. The aircraft was under max landing weight. We exited at the end of the runway and stopped clear of the runway. We queried the Flight Attendant via interphone to assess the situation in the cabin to decide if it was safe to return to the gate or deplane immediately. She informed us that there was not a fire in the cabin. We asked the Emergency Fire Response Unit to assess our condition from the outside. Concluding that it was safe to return to the gate; we ran any appropriate checklists; contacted Company to receive a gate assignment; and clearance from ATC to taxi back to the ramp. The passengers were deplaned; the fire unit came aboard to inspect for fire damage. During this time there was still a haze of smoke in the cabin. Maintenance came aboard; the Captain wrote up the discrepancy. Maintenance and the Captain discussed the event and the aircraft was left with Maintenance.

Data retrieved from NASA's ASRS site as of April 2012 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.