What happened
On August 29, 2013, a Beechcraft A-36, registration PT-JQP, attempted to take off from an unregistered and unpaved gravel airstrip located at Fazenda Rancho Verdura in Iguatemi, Mato Grosso do Sul. The aircraft was operating a private flight with a pilot and three passengers on board, having departed from Presidente Prudente, São Paulo, approximately 70 minutes earlier.
The takeoff roll began from runway 18, which featured an 8-meter uphill gradient. During the takeoff run, the pilot realized the aircraft was not reaching the required rotation speed. Facing obstacles consisting of wire fences immediately beyond the runway threshold, the pilot attempted to maintain flight by deploying full flaps to generate momentary lift. However, the aircraft failed to clear the obstacles effectively, resulting in a loss of altitude and a forced landing. Following the impact, the aircraft struck a fence and a post-crash fire broke out. All four occupants managed to evacuate the wreckage, sustaining light injuries.
The investigation
CENIPA investigators examined the aircraft's performance capabilities and the environmental conditions at the time of the accident. The investigation noted that the aircraft's total weight was approximately 1,562.5 kg. While the aircraft's manuals do not provide specific takeoff performance charts for gravel surfaces, uphill gradients, or specific flap configurations, investigators calculated that on a level, paved runway under similar conditions, a 45 of 450 meters would be required to reach rotation speed.
The investigation established that the use of the gravel surface, the uphill slope, and the high ambient temperature (25°C) significantly increased the required takeoff distance. Additionally, the presence of a left crosswind component and the aircraft's weight contributed to the difficulty in achieving rotation. No mechanical failures were identified, and evidence suggested the engine was producing power at the moment of impact.
Findings
- The takeoff was attempted on an unpaved, unregistered, and unhomologated gravel strip.
- The takeoff roll was performed against an uphill gradient.
- The aircraft's weight, combined with the gravel surface and high temperature, hindered the achievement of rotation speed.
- Inappropriate pilot judgment regarding the decision to continue the takeoff despite insufficient speed.
- Deficiencies in flight planning regarding the takeoff performance on the specific strip conditions.