What happened
On May 13, 2010, a Cessna 150M, registration OK-WWW, crashed into a forested area on the slopes of Javorník peak. The aircraft was performing a VFR flight from Strakonice (LKST) toward the area of Zdíkov. During the flight, the pilot entered weather conditions that were unsuitable for VFR flight, characterized by fog and clouds that obscured the terrain.
The pilot established contact with FIC Praha to request assistance due to the deteriorating visibility. During the communication, the pilot reported being in fog and clouds and was unsure of her exact position. While the controller provided navigational guidance, the pilot failed to maintain the recommended altitude and instead descended into terrain. The aircraft struck trees at an altitude approximately 33 feet below the summit of Javorník, causing the destruction of the aircraft and its subsequent impact on the ground in an inverted position.
The investigation
The ÚZPLN investigation reconstructed the flight path using radar data, radio communication recordings, GPS analysis, and witness statements. The investigation examined the pilot's actions, the controller's instructions, and the meteorological conditions at the time of the accident. The investigation also reviewed the aircraft's mechanical condition and the accuracy of the navigational assistance provided by the flight information service.
Findings
- The pilot entered meteorological conditions that did not meet the minimum requirements for VFR flight.
- The pilot failed to maintain the recommended altitude and continued a descent that led into the terrain.
- The controller mistakenly provided directional vectors toward the wrong aerodrome (LKSR instead of LKST).
- The controller assumed the pilot maintained visual contact with the ground and therefore did not react to deviations from the recommended altitude.
- The pilot's lack of experience and the difficulty in obtaining radar and topographical references contributed to the loss of situational awareness.
- Fog and low cloud cover prevented the pilot from recognizing the rising terrain in time to avoid the collision.
- The aircraft sustained fatal damage due to the impact with tree trunks, specifically to the wing and stabilizer structures.
Safety action
Following the accident, the ÚZPLN issued several safety recommendations to ŘLP ČR, including:
- Evaluating the possibility of providing electronic topographic references to the aircraft's current position at the FIC workstation.
- Enhancing information systems with recommended procedures for emergency and unforeseen situations to provide better assistance to uncontrolled flights in Class G and E airspace.
- Implementing a system for recording background noise at FIC Praha and related ACC workstations.