What happened
During a nighttime flight, an aircraft was observed flying over the southern perimeter of the airport at an altitude between 150 and 200 feet. The aircraft's navigation lights were visible to a witness despite the dark conditions. While executing a left turn to enter the downwind leg of the traffic pattern, the aircraft entered a continuous descent. This maneuver concluded when the aircraft struck the ground in a near-vertical attitude.
As the aircraft transitioned into the turn, the wind conditions shifted from a 10- to 20-knot quartering headwind to a quartering tailwind. The flight path also directed the aircraft toward a rural area characterized by minimal ground lighting.
Findings
An inspection of the engines and the airframe following the accident showed no evidence of mechanical failures or anomalies that would have prevented the aircraft from operating normally prior to the impact.