Investigation Summary
The accident occurred during a multi-leg journey from Sofia to East Berlin. After landing in Bratislava at 11:58 CET to wait out weather in Prague, the crew prepared for departure at 16:20. To maintain separation from a slower Czechoslovak Airlines Il-14 that had just departed, air traffic control cleared Flight 101 to climb to only 300 metres (980 feet) until further notice. The aircraft took off from Runway 31 at 16:28 into total darkness and was instructed to turn right. Instead of clearing the nearby Little Carpathians, the aircraft struck the Sakrakopec hill at an elevation of 420 metres (288 metres above the airport level). The impact was high-speed and occurred with the engines at full take-off power. Rescue efforts were significantly delayed by the difficult terrain, darkness, and a temporary fear that the aircraft was carrying dangerous radioactive isotopes, which were later confirmed to be medical iodine-131 in lead containers.
Final Conclusions
The Czechoslovak commission's final report, supported by ICAO Aircraft Accident Digest No. 16, concluded that the cause could not be definitively established. However, it stated the most probable cause was the crew's insufficient evaluation of the terrain relief and weather conditions in the Bratislava control zone. The report noted the aircraft deviated from the stipulated departure route, possibly due to a wider turn, high speed, or potential crew doubt regarding the artificial horizon's accuracy. The investigation was marked by significant tension between Bulgarian and Czechoslovak officials regarding air traffic control procedures and crew competency.
Photographic Evidence (1)
Video Analysis
No video analysis linked for this case file yet.
Airframe & Maintenance
Crew Experience
Captain
Identified as Commander Antonov.
First Officer
Systems & Failure Modes
Artificial Horizon
Investigators could not rule out that the crew may have doubted the correct operation of this instrument during the turn.
Ivchenko AI-20K Engines
Post-crash analysis confirmed the four turboprop engines were delivering full take-off power at the moment of impact.
Interesting Facts
- 01The crash remains the deadliest aviation accident in the history of modern-day Slovakia.
- 02The aircraft was carrying two steel-lead containers of iodine-131 for medical use, which caused initial hesitation among rescue workers.
- 03The impact occurred at a speed of approximately 250 knots (460 km/h) with no bank angle.
- 04The wreckage was distributed over a swathe 562 metres long.
- 05All 82 occupants, including 74 passengers and 8 crew members, perished in the accident.
Known Controversies & Unanswered Questions
Bulgarian-Czechoslovak Investigative Conflict
Reference ↗A major dispute arose over investigative jurisdiction and liability. Bulgaria accused Bratislava ATC of negligence for failing to monitor the flight on radar, while Czechoslovakia accused the Bulgarian crew of poor English comprehension and failing to follow departure instructions.
Location
ACCIDENT SITE · Coordinates taken from the wikipedia geotag.