Narrative:

Avionic smoke ECAM warning. Got smoke avionics vent fault on the ECAM; while climbing through 10000 ft out of ZZZ. ECAM warning and smell. Declared an emergency with ATC; followed ECAM actions. There was never any visual sign of smoke; but there was a scent of something burning. This smell went away after we completed a few of the ECAM actions. We returned to emergency landing in ZZZ. Overweight landing in ZZZ with weight approximate 164200 pounds. Sink rate at touchdown was about 180 FPM. Landing was normal. Emergency crew did not see any sign of smoke. We then taxied to gate without further event.

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Original NASA ASRS Text

Title: A320 FLT CREW SMELLED SMOKE DURING CLIMBOUT WITH ECAM WARNING FOR AVIONIC SMOKE. EMER DECLARED AND FLT RETURNED TO DEP ARPT.

Narrative: AVIONIC SMOKE ECAM WARNING. GOT SMOKE AVIONICS VENT FAULT ON THE ECAM; WHILE CLBING THROUGH 10000 FT OUT OF ZZZ. ECAM WARNING AND SMELL. DECLARED AN EMER WITH ATC; FOLLOWED ECAM ACTIONS. THERE WAS NEVER ANY VISUAL SIGN OF SMOKE; BUT THERE WAS A SCENT OF SOMETHING BURNING. THIS SMELL WENT AWAY AFTER WE COMPLETED A FEW OF THE ECAM ACTIONS. WE RETURNED TO EMER LNDG IN ZZZ. OVERWT LNDG IN ZZZ WITH WT APPROXIMATE 164200 LBS. SINK RATE AT TOUCHDOWN WAS ABOUT 180 FPM. LNDG WAS NORMAL. EMER CREW DID NOT SEE ANY SIGN OF SMOKE. WE THEN TAXIED TO GATE WITHOUT FURTHER EVENT.

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.