What happened
The pilot arrived at the airport to refuel and pick up a second passenger. After completing refueling and recalculating the weight and balance, the pilot requested an updated weather briefing from AFSS. An IFR flight plan was filed, and the pilot received an IFR clearance along with a void time.
During the period between receiving clearance and departure, a snow squall developed. Prior to takeoff, witnesses observed two passengers sweeping snow from the wings of the aircraft, though they did not observe any cleaning of the horizontal stabilator. While taxiing for departure, the pilot acknowledged UNICOM reports of winds from the east at 8-10 knots. At the time the aircraft departed runway 27, a witness reported visibility was approximately 1/4 mile in heavy snow. Approximately 1/2 mile from the runway, the airplane struck trees.
The investigation
A passenger reported that no engine problems occurred prior to the impact with the trees. The pilot did not report any mechanical deficiencies regarding the engine or the airframe. An on-site examination of the aircraft revealed no mechanical deficiencies with the engine or the airframe.