What happened
On March 10, 2005, at approximately 10:45 UTC, a Cessna 172, registration OK-ABC, operating for BEMOAIR s.r.o., entered the Dubicko Temporary Segregated Area (TSA) while performing a navigational training flight. The aircraft was flying a route from Brno through several locations, including Olomouc and Litovel.
During the flight, the crew encountered snow showers near Litovel and altered their course toward Uničov and Bouzov. In doing so, the aircraft entered the active TSA Dubicko at a heading of 280°, penetrating the restricted airspace by approximately 6 km. At the same time, a military L-39 jet was conducting training maneuvers within the same airspace. The two aircraft came within 6 km of each other, a distance at which there was no opportunity to alert the pilots to the potential conflict. The Cessna 172 remained within the restricted area for approximately eight minutes before exiting.
The investigation
The investigation, conducted by a joint commission from ÚZPLN and the Czech Air Navigation Services, established that the crew of the Cessna 172 had performed pre-flight planning using available online resources. While the pilot checked the AUP for active restricted areas and identified a NOTAM for the Dubicko area, they were unable to locate the specific geographic boundaries of the TSA within the FIR Praha NOTAM summary.
Air Traffic Control (APP EC Přerov) identified the conflict via radar. However, the controller was unable to issue avoidance instructions to the Cessuna 172 because the aircraft was no longer in radio contact with that specific unit. Furthermore, the controller could not immediately access the telephone link to the Forward Air Controller (FAC) to warn the pilot of the L-39 regarding the intruding civilian aircraft.
Findings
- The crew of the Cessna 172 was properly qualified and rated for the flight.
- The aircraft was airworthy with valid maintenance release.
- The primary cause of the incident was insufficient flight information regarding the activation of the TSA obtained by the crew during flight planning and execution.
- The crew was unaware that the airspace near Litovel was currently under the activation of TSA Dubicko.
- Air Traffic Control was unable to intervene due to a lack of direct communication with the civilian aircraft and a lack of immediate access to the military coordination frequency.