Beech D95 N64GM accident near Bahama, North Carolina

Probable cause

The pilots' failure to maintain adequate airspeed during climb, which resulted in the airplane's wing exceeding its critical angle-of-attack and a subsequent aerodynamic stall. Contributing to the accident was the flight instructor's decision to conduct a training flight in an airplane equipped with a single throw-over-type control wheel.

NTSB analysis

The flight instructor, who had recently purchased the multiengine airplane, was providing flight instruction to a non-multiengine-rated private pilot (the student). A witness reported that the flight departed uneventfully, and radar data indicated that the airplane climbed to and leveled off about 1,000 ft above ground level. The airplane's calculated airspeed initially increased to about 130 knots (kts) and then, about 3 minutes into the flight, began to decrease. About 30 seconds later, the airplane began to climb while continuing to lose airspeed. For the final seconds of the flight, the airplane's calculated airspeed was less than 50 kts and close to its expected stall speed. The airplane then entered a rapid descent, and its track deviated to the left.

Examination of the accident site revealed that the airplane impacted trees and terrain in a near-vertical attitude. The airplane's rapid loss of altitude and vertical impact were consistent with the airplane's decaying airspeed resulting in the exceedance of its critical angle-of-attack and a subsequent aerodynamic stall. Examination of the wreckage revealed no evidence of any preimpact mechanical malfunction or failure of the airframe or either engine.

The airplane was equipped with a single throw-over-type control wheel (for elevator and aileron control) and two sets of rudder pedals. The control wheel was found positioned to the left seat, where the student was seated. The student survived the accident but was unable to recall any of the events that transpired during the flight. Thus, the specific sequence of events that resulted in the airplane's eventual aerodynamic stall could not be determined. Regardless, the configuration of the airplane's control wheel would not have allowed the flight instructor to take control of the airplane in order to prevent or recover from the stall.

Text from the NTSB. Open the NTSB docket for ERA15FA023 for the full record.