How so? If I understood correctly the plane brushed treetops as it approached the runway during a storm. Sounds like an error any competent pilot could make, given the circumstances.
From the article . . .
In a series of findings, NTSB investigators concluded that the chartered airplane was flying dangerously slow on its final approach to the airport. The twin-turboprop King Air 100 crashed about 2 miles southeast of the runway on a cloudy morning.
In April, NTSB aerospace engineers released a detailed report that stated the plane had slowed to 76 knots, or 87 miles per hour, seconds before the crash. The plane's flight manual calls for a minimum airspeed in icing conditions of 140 knots.