What happened
On June 28, 2008, a Jabiru SK, registration CS-XAK, was performing a landing at the Tavira aerodrome as part of an air festival. The flight had originated from Azambuja, with a stop in Portimão, following a coastal route under VFR conditions.
As the pilot was established on final approach for runway 12, they spotted a bird on a collision course. In an instinctive attempt to avoid the bird, the pilot maneuvered to the left and lowered the aircraft's nose. During this evasive maneuver, the aircraft struck a medium-voltage electrical transmission line that crossed the approach sector. The impact caused one of the three cables to snap and become entangled with the aircraft, specifically over the engine cowling and beneath the wing. This entanglement caused the aircraft to plummet to the ground approximately 160 meters from the displaced runway threshold.
The aircraft struck several small fruit trees before hitting the ground. Shortly after the occupants evacuated the aircraft, a fire broke out—likely caused by the rupture of fuel tanks and electrical sparking from the power line—which ultimately destroyed the airframe.
The investigation
The GPIAAF investigation examined the flight path, the aircraft's condition, and the local aerodrome infrastructure. The investigation established that the pilot was flying to the aerodrome for the first time and was following instructions provided by the local radio operator.
Investigators analyzed the approach geometry, noting that the safety margins between the aircraft and the power lines were extremely narrow. Calculations showed that even with a standard descent rate, the aircraft would only have passed the lines by approximately 12 to 17 meters. The investigation also reviewed the aerodrome's operational limitations, noting that the physical obstacles at the runway thresholds effectively reduced the usable landing distance to a level below the aircraft's requirements.
Findings
- The primary cause of the accident was the collision with the medium-voltage power line and the subsequent entanglement of a cable, which forced the aircraft into the ground.
- The sudden appearance of a bird necessitated a sharp evasive maneuver.
- The electrical transmission lines were unmarked and lacked any visual warning markers.
- The pilot was unfamiliar with the specific obstacles and operational constraints of the Tavira aerodrome.
- Sunlight positioned directly in front of the pilot further hindered the visibility of the wires.
- The aerodrome's usable runway length was insufficient for the aircraft type, as the presence of obstacles forced a displacement of the thresholds.