Narrative:

On taxi out to runway xy we smelled a plastic burning smell. I also saw a little haze in the cabin. I shut the air conditioning off (the bleed air was not on yet) and told ground we had a problem and wanted to return to the ramp. Shutting off the aircraft didn't help so I decided to shut down the airplane and get everyone off. I told ground I was shutting down and requested assistance.no one was injured and no sign of fire. The flap limit switch was set incorrectly and the flap motor overheated.

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Original NASA ASRS Text

Title: BE20 pilot reported detecting a burning plastic smell on taxi. After shutdown; the odor was attributed to an overheated flap motor.

Narrative: On taxi out to Runway XY we smelled a plastic burning smell. I also saw a little haze in the cabin. I shut the air conditioning off (the bleed air was not on yet) and told Ground we had a problem and wanted to return to the ramp. Shutting off the aircraft didn't help so I decided to shut down the airplane and get everyone off. I told Ground I was shutting down and requested assistance.No one was injured and no sign of fire. The flap limit switch was set incorrectly and the flap motor overheated.

Data retrieved from NASA's ASRS site 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.