What happened
On May 30, 2005, an Air Tractor AT-401, registration EC-EJF, was performing an agricultural spraying operation near Pozoblanco, Córdoba. The aircraft was loaded with 350 liters of fuel and 500 kg of pesticide. The flight was operating from a 600-meter provisional unpaved runway, which was only usable in a West-to-East orientation due to nearby power lines.
During the takeoff roll, the pilot realized the aircraft lacked sufficient speed to safely lift off. As the aircraft reached the end of the runway, the pilot utilized a slight depression in the terrain beyond the runway end to attempt to maintain momentum. The pilot activated the emergency discharge system to reduce weight, which allowed the aircraft to travel approximately 200 meters beyond the runway end. However, the aircraft failed to climb and subsequently struck a stone wall with the landing gear and the left wing tip.
The impact caused the aircraft to spin 180 degrees from its original path. The landing gear was displaced backward, and the main wheels were lost. The left wing sustained heavy damage, and the fuselage buckled toward the left, displacing the vertical stabilizer and rudder. The pilot survived the accident without injury, though the aircraft sustained major damage.
The investigation
The investigation focused on the factors preventing the aircraft from achieving flight. The aircraft was operating below its maximum certified takeoff weight of 3,560 kg, and no engine malfunctions were identified. Investigators examined the environmental conditions, specifically the wind, and the aircraft configuration, specifically the flap settings.
Findings
- The pilot was operating with a tailwind and a slight left crosswind, which increased the required takeoff distance.
- The pilot was forced to use the West-to-East runway orientation because the presence of electrical lines made the reverse direction unusable.
- The selection of near-maximum flap settings created excessive aerodynamic drag, preventing the aircraft from reaching the necessary rotation speed with the available engine power.