Narrative:

[I] encountered smoke in the cockpit from at the time was an unknown source. Immediately started a left hand turn and a descent straight for itr. Immediately contacted ATC and requested priority handling stating possible electrical fire in cockpit. Continued communication long enough to get airport information and request the fire depatment to be on standby and then shut down electrical systems. I opened the crew hatch to get the smoke from the cabin. Landed. Electrical was turned back on just long enough to extend the gear and then was switched back off. After landing I exited the runway and entered ramp area and shut down immediately keeping the plane a safe distance from fuel pumps. After the engines shut down I evacuated the airplane through the open crew hatch and took safety on the other side of the ramp and then contacted the director of operations.

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Original NASA ASRS Text

Title: Air taxi pilot reported that smoke in the cockpit resulted in a diversion.

Narrative: [I] encountered smoke in the cockpit from at the time was an unknown source. Immediately started a left hand turn and a descent straight for ITR. Immediately contacted ATC and requested priority handling stating possible electrical fire in cockpit. Continued communication long enough to get airport information and request the fire depatment to be on standby and then shut down electrical systems. I opened the crew hatch to get the smoke from the cabin. Landed. Electrical was turned back on just long enough to extend the gear and then was switched back off. After landing I exited the runway and entered ramp area and shut down immediately keeping the plane a safe distance from fuel pumps. After the engines shut down I evacuated the airplane through the open crew hatch and took safety on the other side of the ramp and then contacted the Director of Operations.

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.