Accident Details
During landing, the aircraft impacted the runway hard, skidded down the runway, and departed the left side. The left main wheel separated and the nose gear collapsed. Both pilots reported that the landing approach was normal until the aircraft reached approximately 15 feet above the runway, at which point it abruptly descended and impacted hard with the runway. Prior to impact, the aircraft was configured with 20° of flaps, and the landing gear was down and locked. The airspeed was 105 knots.
Aircraft Examination
Post-accident examination disclosed that the aft main gear doors were open and the nose down lock limit switch was defective. This switch is required to close the aft main gear door. A flight test by the manufacturer determined that an opened aft main gear door has none to unnoticeable effect on stall speed. The aircraft speed at touchdown, based on computations from propeller slash marks, was 86 knots. The stall speed at the prevailing weight and flap configuration was below this speed; the aircraft weight was approximately 9,000 lbs.
Probable Cause
The official findings list the following probable causes: Loss of control in flight (reason undetermined); proper descent rate exceeded; hard landing (level off not possible by pilot); gear collapsed due to overload of the main and nose landing gear.