Narrative:

During takeoff at approximately 500 ft AGL; the first officer and I noticed smoke in the cockpit; with the odor of something burning. About 30 seconds after this; we received the lavatory smoke message on the EICAS. Immediately after that the flight attendant called to say that there was smoke in the cabin and that the smoke alarm was going off. We declared the emergency and returned to the same runway that we took off from. We made an overweight landing at approximately 500 FPM descent rate and evacuate/evacuationed the airplane on the runway.

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Original NASA ASRS Text

Title: EMB145 FLT CREW HAS SMOKE AND OR FUMES IN THE COCKPIT; DECLARES EMER AND RETURNS FOR LNDG.

Narrative: DURING TKOF AT APPROX 500 FT AGL; THE FO AND I NOTICED SMOKE IN THE COCKPIT; WITH THE ODOR OF SOMETHING BURNING. ABOUT 30 SECONDS AFTER THIS; WE RECEIVED THE LAVATORY SMOKE MESSAGE ON THE EICAS. IMMEDIATELY AFTER THAT THE FLT ATTENDANT CALLED TO SAY THAT THERE WAS SMOKE IN THE CABIN AND THAT THE SMOKE ALARM WAS GOING OFF. WE DECLARED THE EMER AND RETURNED TO THE SAME RWY THAT WE TOOK OFF FROM. WE MADE AN OVERWT LNDG AT APPROX 500 FPM DSCNT RATE AND EVACED THE AIRPLANE ON THE RWY.

Data retrieved from NASA's ASRS site as of January 2009 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.