What happened
On June 15, 2004, at approximately 08:40 UTC, a Piper PA-36-375 (registration CS-AZU) was performing an agricultural mission near Samora Correia, Portugal. The aircraft, operated by AVITRATA, had flown from its base in Benavente to the Porto Alto agricultural landing strip to refuel with chemical products for a crop treatment mission.
Upon arrival, the pilot attempted to land on runway 08. Relying on previous knowledge of the site and observing tracks on the ground, the pilot positioned the aircraft slightly to the left of the centerline to avoid perceived earth mounds on the right side of the strip. During the landing roll, the aircraft's left wing struck large bushes located on the runway shoulder. This impact caused the aircraft to veer left, crossing a drainage ditch and climbing an embankment. The aircraft subsequently struck the ground with its propeller, causing the right main landing gear to fracture and detach, and the tailwheel to break. The aircraft slid approximately five meters before coming to a halt roughly 280 meters from the start of the runway.
The investigation
The GPIAAF investigation examined the aircraft, the pilot's credentials, and the operational procedures of the operator. The investigation confirmed that the aircraft was well-maintained and that the pilot held a valid commercial license with appropriate ratings for agricultural work. The investigation also reviewed the landing strip conditions and the operator's flight manual (MOV).
Investigators found that the pilot had not performed a recent reconnaissance of the landing strip or a low-altitude flyover to verify the current state of the runway. While the pilot relied on information from previous operations, the vegetation at the edge of the strip had grown to a height exceeding the aircraft's wing clearance, and the strip no longer met the minimum safety width requirements specified in the operator's manual.
Findings
- The primary cause of the accident was the failure to perform a prior inspection of the aerodrome and its operational conditions as required by the operator's flight manual.
- The pilot relied on outdated information regarding the runway state, assuming the strip was clear based on previous experience.
- The presence of dense, tall vegetation on the runway shoulders significantly reduced the usable width of the landing strip.
- The existence of an embankment alongside the runway left no margin for error during a runway excursion.
- The aircraft sustained extensive damage, including a broken propeller, damaged engine cowlings, a fractured right main gear, and damage to the vertical stabilizer and rudder.