Narrative:

On departure climb out at 8;000 the first officer and I noticed a strong electric burning smell. Shortly thereafter we heard commotion (movement and yells) in the cabin of the aircraft followed by multiple call button tones from passengers. The #3 flight attendant called the cockpit and notified us that passengers were yelling there was smoke and it smelled like electrical fire. She reported: the smoky area was isolated in the center portion of the cabin (row 20). She had initially thought it was condensation; but after getting closer (she went to row 20) it was obvious to be smoke and burnt electrical. We notified ATC and leveled the aircraft at 11;000; the smell began to dissipate; but there was still an electrical smell lingering. At this point; the first officer and I deemed that the smoke or smell was not strong enough in the cockpit area to don oxygen masks or goggles. Also; due to the smoke and smell dissipation; I determined the QRH procedure was not required. I verified the reports twice with the # 1 flight attendant and also verified that the smoke and smell was dissipating. At this point; I determined and conferred with the first officer that the best course of action was to return to the airport. I declared an emergency with ATC; notified the #1 flight attendant; briefed the passengers; and notified company we were returning. Upon inspection by maintenance; the problem was isolated to a blown/burned light ballast in row 20. Side note: after arriving; I was informed by maintenance that this was not the first occasion with our aircraft fleet and that it could (a theory) be related to the 166 seat conversion wiring. Of course this was theory; but seemed worthy of noting.

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Original NASA ASRS Text

Title: Shortly after takeoff a MD-83 crew and passengers detected a strong electrical burning smell with smoke in the cabin; so an emergency was declared and the flight returned to the departure airport where a burnt florescent light ballast was found in row 20.

Narrative: On departure climb out at 8;000 the First Officer and I noticed a strong electric burning smell. Shortly thereafter we heard commotion (movement and yells) in the cabin of the aircraft followed by multiple call button tones from passengers. The #3 Flight Attendant called the cockpit and notified us that passengers were yelling there was smoke and it smelled like electrical fire. She reported: The smoky area was isolated in the center portion of the cabin (row 20). She had initially thought it was condensation; but after getting closer (she went to row 20) it was obvious to be smoke and burnt electrical. We notified ATC and leveled the aircraft at 11;000; the smell began to dissipate; but there was still an electrical smell lingering. At this point; the First Officer and I deemed that the smoke or smell was not strong enough in the cockpit area to don oxygen masks or goggles. Also; due to the smoke and smell dissipation; I determined the QRH procedure was not required. I verified the reports twice with the # 1 Flight Attendant and also verified that the smoke and smell was dissipating. At this point; I determined and conferred with the First Officer that the best course of action was to return to the airport. I declared an emergency with ATC; notified the #1 Flight Attendant; briefed the passengers; and notified Company we were returning. Upon inspection by Maintenance; the problem was isolated to a blown/burned light ballast in row 20. Side note: After arriving; I was informed by Maintenance that this was not the first occasion with our aircraft fleet and that it could (a theory) be related to the 166 seat conversion wiring. Of course this was theory; but seemed worthy of noting.

Data retrieved from NASA's ASRS site as of July 2013 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.