Narrative:

During passenger boarding smoke began to pour out of the radar/TCAS indicator. Flight crew immediately de-powered the aircraft and the smoke stopped. We stopped boarding the aircraft and directed the flight attendant to deplane the twenty or so passengers who were on board. We called maintenance and they took over from there. The radar/TCAS indicator had an electrical short.

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Original NASA ASRS Text

Title: A B757 air carrier Captain reported his radar/TCAS indicator began smoking during passenger boarding. Power was removed from the aircraft and maintenance was called.

Narrative: During passenger boarding smoke began to pour out of the Radar/TCAS indicator. Flight crew immediately de-powered the aircraft and the smoke stopped. We stopped boarding the aircraft and directed the Flight Attendant to deplane the twenty or so passengers who were on board. We called Maintenance and they took over from there. The Radar/TCAS indicator had an electrical short.

Data retrieved from NASA's ASRS site as of April 2012 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.