What happened
On June 15, 2004, at approximately 19:30, an Air Tractor AT-802, registration EC-IOE, was performing an aerial firefighting mission from an improvised dirt airstrip at El Maíllo, Salamanca. The aircraft, operated by Faasa Aviación, was heavily loaded with approximately 600 gallons of water and over 1,000 liters of fuel for an active fire response.
During the takeoff roll, the pilot attempted to rotate the aircraft after reaching approximately 80 mph. However, the aircraft failed to gain further speed and the tail failed to lift despite the pilot's efforts. The pilot noted that the aircraft's acceleration had ceased. Faced with a lack of remaining runway and obstacles such as a fence and a ravine ahead, the pilot attempted to lower the nose to regain speed and lighten the water load. Ultimately, the aircraft could not achieve sufficient lift and impacted the ground approximately 300 meters beyond the end of the runway. The pilot escaped the aircraft without injury.
The investigation
The investigation examined the aircraft's mechanical condition, the runway characteristics, and the performance calculations for the specific flight conditions. Investigators inspected the engine and propeller, finding no evidence of mechanical failure; the propeller showed signs of impact consistent with the engine being at power upon landing. The aircraft's maintenance records were found to be up to date.
Analysis of the runway revealed it was an 800-meter unpaved strip with an uphill gradient, bumps, and patches of vegetation. While the aircraft's weight of approximately 14,500 lb was below the maximum authorized takeoff weight for the altitude and temperature, the investigation compared the required takeoff distance against the available runway length. The study concluded that the combination of the uphill slope, the unpaved surface, and the heavy load created a requirement for a takeoff distance that was critically tight for the available runway.
Findings
- The aircraft did not reach the necessary airspeed to rotate and lift off within the available runway distance.
- Several factors contributed to reduced acceleration, including the uphill gradient of the runway, the bumpy and unpaved surface, and the heavy weight of the water and fuel loads.
- The investigation noted that the available runway length was extremely limited for the specific environmental and weight conditions of the operation.