What happened
On March 26, 2004, a PIPER PA-118-150, registration EC-ALK, was conducting a flight training mission consisting of takeoff and landing practice at the Casarrubios del Monte aerodrome in Toledo, Spain. The flight was operated by an instructor and a student pilot.
During the final takeoff attempt on runway 08, the crew noted vibrations in the tail section following a landing. As the pilot applied power to initiate the takeoff roll, the aircraft suddenly veered to the left at a 60-degree angle. The crew attempted to correct the deviation using rudder and right braking, but the aircraft continued to skid at a 45-degree angle relative to the runway centerline.
As the aircraft left the paved surface, it traveled 25 meters on the runway before exiting the pavement. Once off the runway, the aircraft traveled an additional 55.6 meters across uneven terrain. The left main gear struck a depression in the ground, causing the aircraft to lose momentum and eventually capsize. Both occupants evacuated the aircraft without injury.
The investigation
The CIAIAC investigation examined the aircraft's steering mechanics, the runway environment, and the flight sequence. Investigators analyzed the tracks left on the runway and the surrounding terrain, noting that the tailwheel left sinusoidal marks on the asphalt, indicating a skid.
Technical inspection of the tailwheel assembly revealed no mechanical failures or anomalies; the steering was functioning within its normal operational parameters. The investigation also assessed the condition of the runway safety area, finding that recent rains had caused significant soil erosion, resulting in ruts and depressions ranging from 20 to 60 centimeters deep in the area beyond the runway edge.
Findings
- The primary cause of the deviation was the misalignment of the tailwheel relative to the aircraft's longitudinal axis, consistent with rudder input by the crew.
- The high speed of the aircraft during the initial deviation made directional control difficult to recover.
- The decision by the crew to continue the takeoff attempt after the aircraft had already drifted off the paved surface increased the risk of structural damage.
- The uneven terrain and deep ruts located beyond the runway safety strip contributed to the impact on the landing gear and the eventual capsize of the aircraft.