Departure and Communications
The airplane was departing into instrument meteorological conditions using a standard instrument departure, which consisted of a climbing right turn direct to a nondirectional beacon. After departure, the pilot radioed an air traffic controller asking if he would be told when to turn. The controller replied that he would not call the turn and that the pilot should fly the departure as published, making a climbing right turn to overfly the approach end of the runway. The pilot acknowledged this communication, which was his last transmission.
Flight Path and Impact
Following the acknowledgment, the airplane made a 360° turn and descended below the cloud layer. It then climbed back into the cloud layer and performed an inverted loop, descending into the ground in a near-vertical attitude.
Postaccident Examination
A postaccident examination of the airplane revealed no evidence of preimpact mechanical malfunctions or failures. Recorded audio from before the accident was consistent with the engines operating. The signatures on both propellers were consistent with one another and with the engines operating at a similar rpm.
Pilot Information
The pilot was qualified and had recently undergone recurrent training. The reasons the pilot became spatially disoriented could not be definitely determined. The pilot left the anti-collision lights on while in the clouds, which may have resulted in flicker vertigo.