What happened
On October 23, 2021, a pilot operating a Schempp-Hirth Ventus 2CT glider departed from Vitacura Municipal Aerodrome for a recreational flight toward Los Andes. During the flight, the pilot encountered significant meteorological challenges, including thermal inversions that prevented the aircraft from climbing above 2,000 meters.
While navigating the mountainous terrain near Cerro La Trucha, the pilot attempted to cross a mountain ridge from south to north at a low altitude. During this maneuver, the aircraft encountered high-voltage power lines positioned parallel to the northern slope. Due to encountering descending air currents and being unable to clear the obstacle from above, the pilot executed an emergency landing in the narrow space between the electrical lines and the mountain slope. The impact with the irregular, sloping terrain resulted in serious injuries to the pilot and extensive damage to the aircraft.
The investigation
The DGAC Chile investigation examined the flight trajectory, meteorological conditions, and the aircraft's configuration. Investigators analyzed the impact site, noting that the aircraft's landing gear was retracted during the emergency landing. The investigation also reviewed the use of water ballast, as the pilot had loaded approximately 20 to 25 liters of water in each wing to improve performance.
Technical inspections of the Schempp-Hirth Ventus 2CT revealed significant structural damage, including fractures to the fuselage, canopy, tail cone, and wing spars, as well as damage to the control surfaces. The investigation also looked into the pilot's decision-making process regarding the decision to continue the flight into mountainous terrain despite the presence of thermal inversions and the decision not to utilize the aircraft's onboard motor or jettison the water ballast to assist in climbing.
Findings
- The primary cause was conducting a glider flight in weak thermal conditions that prevented sufficient altitude gain, necessitating an emergency landing.
- The pilot's decision to continue toward the mountains despite the inability to climb through thermal inversions contributed to the encounter with the obstacle.
- Descending air currents on the leeward side of the ridge prevented the aircraft from clearing the high-voltage lines.
- The aircraft was flying at a low altitude and low speed during the crossing.
- The pilot did not utilize available resources, such as the onboard motor or the jettisoning of water ballast, to mitigate the adverse flight conditions.
- The severity of the pilot's injuries was due to the direct impact of the fuselage against the irregular terrain following the landing.