What happened
The pilot filed an instrument flight plan for the flight but failed to request and receive clearance prior to departure. At the time of the accident, visibility was reported at less than 1/4 mile.
Witnesses observed the aircraft depart from runway 18 and execute a right turn. Following this maneuver, witnesses reported hearing "a big crackling noise." Notably, those present noted that the engine did not produce any unusual sounds prior to the noise. The terrain located west of the airport rises between 300 and 400 feet within 1,500 feet of the runway centerline.
The published instrument departure procedure for runway 18 requires a climb on a heading of 170 degrees until reaching 1,200 feet MSL, after which the aircraft is to proceed on course. Although the pilot had recently completed a recurrent instrument training program and was familiar with the airport's departure procedures, the failure to obtain clearance preceded the event.