What happened
The pilot initiated a takeoff roll from a 3539-foot runway that was both wet and upsloping. The aircraft was loaded to approximately 9300 pounds, which was about 300 pounds under the maximum gross weight limit. A flap setting of 5 degrees was selected for departure.
During the ground roll, the pilot reported that the aircraft accelerated but failed to reach the target speed of 107 knots. After traveling approximately 2700 feet along the runway, the decision was made to abort the takeoff. The pilot deployed both propellers into reverse thrust and applied full braking force.
Despite these efforts, the aircraft continued moving past the departure end of the runway. It penetrated a perimeter fence, crossed a four-lane road and its median strip, struck a utility pole, and ultimately impacted a large tree located about 850 feet beyond the runway threshold.
The investigation
A review of the aircraft's performance manual indicated that the required takeoff distance to clear a 50-foot obstruction was 1900 feet. The manual recommended accelerating to between 70 and 80 knots before applying back pressure on the elevator control, with an expected lift-off speed of 93 to 96 knots for either 5 or 20 degrees of flap settings.
Mechanical inspection revealed no evidence of powerplant or control system malfunctions that would have contributed to the incident.
Findings
The primary factors leading to the accident were the wet and upsloping runway conditions which degraded acceleration performance. The aircraft was unable to achieve sufficient speed within the available runway length, resulting in a runway overrun. The pilot's decision to continue the takeoff roll despite inadequate acceleration contributed to the loss of control and subsequent collision with stationary objects.
Safety message
Pilots must carefully evaluate runway conditions, particularly when surfaces are wet or have an upslope gradient. These factors significantly increase ground roll distances and reduce acceleration rates. Aborting a takeoff early, if performance targets are not met, is critical to avoiding overruns on constrained airfields.