Narrative:

Smoke and fumes in cockpit. No fumes in cabin. Declared emergency, ran QRH. Turned back to aua all at the same time. Smoke and fumes disappeared very quickly when checklist was complied with, but fumes returned momentarily, +/-15000 ft. Uneventful landing. Found right re-circulation fan inoperative.

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Original NASA ASRS Text

Title: A B757 FLT CREW DECLARE AN EMER AND DIVERT BACK TO TNCA DUE TO SMOKE AND FUMES IN THE COCKPIT.

Narrative: SMOKE AND FUMES IN COCKPIT. NO FUMES IN CABIN. DECLARED EMER, RAN QRH. TURNED BACK TO AUA ALL AT THE SAME TIME. SMOKE AND FUMES DISAPPEARED VERY QUICKLY WHEN CHKLIST WAS COMPLIED WITH, BUT FUMES RETURNED MOMENTARILY, +/-15000 FT. UNEVENTFUL LNDG. FOUND R RE-CIRCULATION FAN INOP.

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.