What happened
On July 5, 2002, at 17:15 local time, an Air Tractor AT-802, registration EC-GZO, was performing a landing at Sabadell Airport following a forest surveillance mission. The aircraft touched down on runway 13 in a three-point position, aligned with the runway centerline.
After traveling approximately 50 meters down the runway, the aircraft began a sharp turn to the right. The pilot attempted to correct the deviation using the brakes and rudder, and subsequently applied reverse thrust and brakes to prevent the aircraft from exiting the runway. During the maneuver, the left main landing gear tire burst, causing the aircraft to skid. This led to the collapse of the left main gear, causing the left wing and propeller to impact the ground. The aircraft eventually came to a stop on the right side of the runway, oriented at a heading of 280 degrees. The two occupants of the aircraft were uninjured.
The investigation
The investigation examined the aircraft's maintenance records, the meteorological conditions at the time of the accident, and the mechanical state of the landing gear. The aircraft's airworthiness certificate was valid, and maintenance had been performed according to the required program. Post-accident inspections of the aircraft systems revealed no mechanical anomalies other than the damage caused by the impact.
Investigators also reviewed weather data from the National Institute of Meteorology (INM). While the pilot had been informed of a 10-knot crosswind from 220 degrees, meteorological records indicated that wind gusts had reached up to 17 knots between 14:50 and 15:00 UTC. Additionally, the air traffic controller reported that the tailwheel was unlocked during the landing roll, which caused it to oscillate.
Findings
- The aircraft was operating within its maximum allowable crosswind limit of 20 knots, though the wind gusts were near this threshold.
- The wind gust was the primary factor that caused the aircraft to lose directional control.
- The unlocked tailwheel likely contributed to the loss of control by allowing the aircraft to act like a weather vane, exacerbating the rightward turn.
- The impact caused significant damage to the left wing, flaps, ailerons, and the propeller, as well as damage to the runway asphalt.