Narrative:

On VFR offline training flight began noticing faint smoke smell about a minute after passing the FAF on the VOR approach. Smell slowly became more prominent and decision was made that after landing we'd discontinue the flight and return to the ramp to shut down. After landing received taxi clearance from ground and proceeded to taxi. Also after landing we observed the gear-handle 'J-hook' rapidly engage and disengage several times. During taxi smell rapidly intensified into a pungent burning electrical smell and approximately 60 seconds after landing visible smoke began to enter the cockpit from behind. Performed electrical fire checklist (all electrical off) and opened cockpit windows to increase ventilation as smoke rapidly intensified. As we entered ramp smoke became noxious and chokingly thick and as soon as we were clear of the taxiway I instructed the trainee to shutdown both engines and evacuate via the cockpit door. Before getting out myself I quickly turned the master back on to notify ground that we had smoke in the cockpit and needed the fire trucks; then turned it back off and evacuated myself. Opened all doors to ventilate aircraft and found entire cabin had filled with smoke. Fire department arrived and investigated aircraft; noting that the smoke was indeed electrical and very strong; but couldn't determine source. Scanned exterior of aircraft with thermal camera but could not detect any obvious hotspots. I called dispatch and notified them of the situation. Later maintenance came out and after discussing what had happened they inspected the gear motor and found it too hot to touch (30 minutes after shutdown).

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Original NASA ASRS Text

Title: The pilot of a Beechcraft 99 reported smoke and smell in the aircraft during a training flight that resulted in a return to the departure airport and crew evacuation.

Narrative: On VFR offline training flight began noticing faint smoke smell about a minute after passing the FAF on the VOR approach. Smell slowly became more prominent and decision was made that after landing we'd discontinue the flight and return to the ramp to shut down. After landing received taxi clearance from Ground and proceeded to taxi. Also after landing we observed the gear-handle 'J-hook' rapidly engage and disengage several times. During taxi smell rapidly intensified into a pungent burning electrical smell and approximately 60 seconds after landing visible smoke began to enter the cockpit from behind. Performed electrical fire checklist (all electrical off) and opened cockpit windows to increase ventilation as smoke rapidly intensified. As we entered ramp smoke became noxious and chokingly thick and as soon as we were clear of the taxiway I instructed the trainee to shutdown both engines and evacuate via the cockpit door. Before getting out myself I quickly turned the master back on to notify ground that we had smoke in the cockpit and needed the fire trucks; then turned it back off and evacuated myself. Opened all doors to ventilate aircraft and found entire cabin had filled with smoke. Fire department arrived and investigated aircraft; noting that the smoke was indeed electrical and very strong; but couldn't determine source. Scanned exterior of aircraft with thermal camera but could not detect any obvious hotspots. I called dispatch and notified them of the situation. Later maintenance came out and after discussing what had happened they inspected the gear motor and found it too hot to touch (30 minutes after shutdown).

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.