Background
The aircraft was operating under an instrument flight plan. Prior to departure, the pilot received a weather briefing that included an area of weather located at the aircraft's twelve o'clock position, four miles ahead. The weather area extended thirty miles southwest and was twenty miles wide.
Flight History
During the flight, the pilot reported that one engine was slightly hot or running roughly. The aircraft was cleared to Shreveport, received radar vectors, and began a descent. Radio and radar contact was lost when the aircraft was at approximately 4,000 feet.
Post-Impact Examination
Examination of the wreckage revealed no malfunctions in either engine. No known mechanical or system malfunctions were identified with the aircraft. However, the filament of the tail light bulb showed no evidence of direct current being applied at the time of impact, suggesting a possible loss of DC electrical power before the crash.
The aircraft impacted the surface in a near-vertical, nose-down attitude.
Possible Factors
Investigators noted the possibility that an inflight loss of DC power may have caused the pilot to lose control of the aircraft during dark night and turbulent instrument conditions. Another possibility considered was inadvertent activation of the crash bar, resulting in a total loss of electrical power. Additionally, there was mention of possible passenger motion sickness, though its relevance to the accident was not specified.
No probable cause was determined, as the investigation listed only possibilities.