Narrative:

On takeoff roll and initial climb out, a rancid odor came into the cockpit. It smelled like something had died and smelled similar to sewage. No electrical or burning smell was noticed at this time. The flight attendants called us immediately on climb out and notified us of a very strong foul odor in the cabin, especially the rear of the cabin. After another call complaining of the continued strong odor and 'haze' we leveled off at 5000 ft, declared an emergency and turned left to 360 degrees to return to atl. The autoplt was inoperative, so I hand flew the airplane. The captain coordinated with the flight attendants and ATC for a return to atl. I flew a visual to runway 8L to a full stop. The smell dissipated in the cockpit and basically went away. I never saw any smoke in the cockpit but the flight attendants said it got a little 'hazy' in the very back of the cabin. After landing and pulling off the runway we did smell something electrical, but only for 30 seconds or so and then cleared up. The fireman lowered the rear airstairs and the passenger slowly and orderly evacuate/evacuationed the airplane only down the rear airstairs.

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Original NASA ASRS Text

Title: THE CABIN ATTENDANT RPTED SMOKE AND FUMES IN THE CABIN WHICH WAS ALSO SMELLED IN THE FLT STATION. THE CAPT DECLARED AN EMER AND RETURNED TO POINT OF DEP.

Narrative: ON TKOF ROLL AND INITIAL CLBOUT, A RANCID ODOR CAME INTO THE COCKPIT. IT SMELLED LIKE SOMETHING HAD DIED AND SMELLED SIMILAR TO SEWAGE. NO ELECTRICAL OR BURNING SMELL WAS NOTICED AT THIS TIME. THE FLT ATTENDANTS CALLED US IMMEDIATELY ON CLBOUT AND NOTIFIED US OF A VERY STRONG FOUL ODOR IN THE CABIN, ESPECIALLY THE REAR OF THE CABIN. AFTER ANOTHER CALL COMPLAINING OF THE CONTINUED STRONG ODOR AND 'HAZE' WE LEVELED OFF AT 5000 FT, DECLARED AN EMER AND TURNED L TO 360 DEGS TO RETURN TO ATL. THE AUTOPLT WAS INOP, SO I HAND FLEW THE AIRPLANE. THE CAPT COORDINATED WITH THE FLT ATTENDANTS AND ATC FOR A RETURN TO ATL. I FLEW A VISUAL TO RWY 8L TO A FULL STOP. THE SMELL DISSIPATED IN THE COCKPIT AND BASICALLY WENT AWAY. I NEVER SAW ANY SMOKE IN THE COCKPIT BUT THE FLT ATTENDANTS SAID IT GOT A LITTLE 'HAZY' IN THE VERY BACK OF THE CABIN. AFTER LNDG AND PULLING OFF THE RWY WE DID SMELL SOMETHING ELECTRICAL, BUT ONLY FOR 30 SECONDS OR SO AND THEN CLRED UP. THE FIREMAN LOWERED THE REAR AIRSTAIRS AND THE PAX SLOWLY AND ORDERLY EVACED THE AIRPLANE ONLY DOWN THE REAR AIRSTAIRS.

Data retrieved from NASA's ASRS site as of July 2007 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.