Narrative:

XX35Z, lax departure, 10000 ft. Socal departure, 249 degree radial, 5 DME. During climb out from lax, smoke began entering the cockpit and cabin. Attempted to isolate the problem by emergency checklist. Declared an emergency and returned to lax. Landed overweight, 139600 pounds. Normal touchdown. Smoke in cockpit cabin and overweight landing entered in logbook.

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Original NASA ASRS Text

Title: AN S80 DEPARTING LAX HAS SMOKE ENTERING CABIN AND COCKPIT. AN EMER IS DECLARED AND THE ACFT RETURNS TO LAND AT LAX.

Narrative: XX35Z, LAX DEP, 10000 FT. SOCAL DEP, 249 DEG RADIAL, 5 DME. DURING CLBOUT FROM LAX, SMOKE BEGAN ENTERING THE COCKPIT AND CABIN. ATTEMPTED TO ISOLATE THE PROB BY EMER CHKLIST. DECLARED AN EMER AND RETURNED TO LAX. LANDED OVERWT, 139600 LBS. NORMAL TOUCHDOWN. SMOKE IN COCKPIT CABIN AND OVERWT LNDG ENTERED IN LOGBOOK.

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.