Narrative:

I was in cruise at 18;000 when I noticed out of the corner of my eye 'something.' upon closer inspection it was a tiny tendril of smoke coming from under the lower edge of the right side of the panel. Within just a few seconds smoke began to billow up from under the panel. I called ATC and [told] them that I had smoke in the cockpit. I had a moving map up on an ipad running garmin pilot connected to a gdl 39 as well as the map up on the garmin 530W both of which indicated that [a nearby airport] was close. ATC was asking if I wanted to go to nearest; I answered yes and that I was going to shut off all power and would talk to them on ground. I then shut off power to avionics. I left the ipad and gdl running since they were separate from plane power. After extending gear and flaps to max I shut off battery and alternator power as well. I then reduced power to idle on the engines as well as setting the props to flat pitch; then descended as fast as I could while keeping the airspeed within the green arc. I had not noticed that upon killing the avionics master the smoke diminished and eventually stopped. My focus was getting the plane down in one piece.I landed on the first available runway and now noticed that the smoke had stopped so I taxied to a parking spot; shut down; and evacuated the plane. I called clearance on my mobile and let them know that I was on the ground safely. Called center about 15 minutes later to let them know what had happened. I think that the entire incident from noticing the smoke to stopped on ground took less than 5 minutes. It was found that the bearings to a cooling fan had frozen causing the power leads to scorch. No damage to the plane.

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Original NASA ASRS Text

Title: Twin Cessna Pilot reported a an electrical fire in flight. Pilot shut down all electrics and landed at a nearby field.

Narrative: I was in cruise at 18;000 when I noticed out of the corner of my eye 'something.' Upon closer inspection it was a tiny tendril of smoke coming from under the lower edge of the right side of the panel. Within just a few seconds smoke began to billow up from under the panel. I called ATC and [told] them that I had smoke in the cockpit. I had a moving map up on an iPad running Garmin Pilot connected to a GDL 39 as well as the map up on the Garmin 530W both of which indicated that [a nearby airport] was close. ATC was asking if I wanted to go to nearest; I answered yes and that I was going to shut off all power and would talk to them on ground. I then shut off power to avionics. I left the iPad and GDL running since they were separate from plane power. After extending gear and flaps to max I shut off battery and alternator power as well. I then reduced power to idle on the engines as well as setting the props to flat pitch; then descended as fast as I could while keeping the airspeed within the green arc. I had not noticed that upon killing the avionics master the smoke diminished and eventually stopped. My focus was getting the plane down in one piece.I landed on the first available runway and now noticed that the smoke had stopped so I taxied to a parking spot; shut down; and evacuated the plane. I called clearance on my mobile and let them know that I was on the ground safely. Called Center about 15 minutes later to let them know what had happened. I think that the entire incident from noticing the smoke to stopped on ground took less than 5 minutes. It was found that the bearings to a cooling fan had frozen causing the power leads to scorch. No damage to the plane.

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.