What happened
On August 15, 2006, at approximately 19:40 local time, an Air Tractor AT-802, registration EC-HNK, was engaged in aerial firefighting operations near the Mijares port in Ávila, Spain. The aircraft had departed from La Iglesuela runway at 19:30 to assist in extinguishing a wildfire.
While climbing through a valley, the pilot determined that the aircraft's climb rate was insufficient to clear the terrain at the end of the valley. After verifying that engine torque, propeller RPM, ITT, and airspeed were within normal parameters, the pilot increased torque and propeller pitch to attempt a steeper climb. Realizing the aircraft would not safely clear the pass, the pilot decided to jettison the water load and execute a turn to return.
The pilot initiated a right turn of approximately 15 to 20 degrees toward the valley wall, followed by a left turn with a low nose to regain airspeed. During this maneuver, the aircraft reached a 150-degree bank when a sudden descent occurred. Facing an imminent impact, the pilot leveled the aircraft and directed it toward an area intended to mitigate the force of the crash. The aircraft struck a small wooded area containing roughly 15 to 20 trees, losing energy through successive impacts before coming to a stop. A fire subsequently broke out, spreading to nearby vegetation. The pilot successfully exited the aircraft through the left window before it came to a complete halt.
The investigation
The CIAIAC investigation examined the wreckage, the pilot's statements, and maintenance records. Due to the destruction of the aircraft and the subsequent fire, a detailed study of the wreckage was not possible. However, the investigation found no evidence of mechanical failure prior to the accident. The pilot reported that all engine and flight instruments were operating normally.
Investigators also considered meteorological conditions, noting good visibility and no clouds, though strong winds were present. While localized downdrafts or wind effects on the leeward side of the valley were considered, they were deemed too low in intensity to be the primary cause. The investigation also looked into the aircraft's weight, noting the possibility that the aircraft was carrying more load than in previous flights, though the pilot was unaware of any significant weight discrepancy.
Findings
- The aircraft was operating in a climb phase within a valley, attempting to clear terrain.
- The pilot attempted a low-speed maneuvering turn to avoid terrain, which resulted in a loss of altitude.
- The aircraft entered the valley at a lower altitude than in previous successful flights, which prevented the pilot from clearing the pass or completing the turn safely.
- There were no indications of mechanical or system failures prior to the impact.