Narrative:

Discovered smoke in cockpit 3 mins after takeoff, followed by call from cabin reporting smoke throughout cabin. Turned off packs 1 and 2, opened ram air inlet. Captain elected to declare an emergency and return to iah. Completed return uneventfully. Smoke was clearing in the cabin by the time landing was made. No electrical or oil smell was detected. Smoke in the cabin reported as grayish. No emergency or caution lights illuminated. Callback conversation with reporter revealed the following: confirmed that the problem was in the air conditioning system. Second officer said the water bag filters were dirty and clogged. The cabin attendant indicated the smoke was irritating to breath. Filters cleaned and flight continued.

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Original NASA ASRS Text

Title: SMOKE DETECTED IN THE CABIN AND COCKPIT OR ACR WDB SHORTLY AFTER TKOF. EMERGENCY DECLARED. RETURN LAND.

Narrative: DISCOVERED SMOKE IN COCKPIT 3 MINS AFTER TKOF, FOLLOWED BY CALL FROM CABIN REPORTING SMOKE THROUGHOUT CABIN. TURNED OFF PACKS 1 AND 2, OPENED RAM AIR INLET. CAPT ELECTED TO DECLARE AN EMER AND RETURN TO IAH. COMPLETED RETURN UNEVENTFULLY. SMOKE WAS CLEARING IN THE CABIN BY THE TIME LNDG WAS MADE. NO ELECTRICAL OR OIL SMELL WAS DETECTED. SMOKE IN THE CABIN REPORTED AS GRAYISH. NO EMER OR CAUTION LIGHTS ILLUMINATED. CALLBACK CONVERSATION WITH REPORTER REVEALED THE FOLLOWING: CONFIRMED THAT THE PROBLEM WAS IN THE AIR CONDITIONING SYSTEM. S/O SAID THE WATER BAG FILTERS WERE DIRTY AND CLOGGED. THE CAB INDICATED THE SMOKE WAS IRRITATING TO BREATH. FILTERS CLEANED AND FLT CONTINUED.

Data retrieved from NASA's ASRS site as of August 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.