The accident is being investigated by the Czech Air Accidents Investigation Institute (ÚZPLN), which will issue a final report upon completion of its official inquiry. However, based on the information currently available, the probable cause is believed to be an unsecured canopy prior to takeoff.
What We Know So Far
The pilot, who held an ultralight pilot qualification, had rented the aircraft for a private flight with one passenger. He conducted a pre-flight inspection and, after starting the engine, taxied to the holding point for runway 05R. Following a smooth takeoff roll and liftoff, the aircraft briefly touched down on the runway again—first lightly, then more heavily. The pilot continued the climb and reported an issue with the canopy. At an altitude of approximately 100 metres above ground level (AGL), he initiated a left turn back towards the reciprocal runway 23. At low airspeed and a high bank angle, the aircraft entered a spin and impacted the ground after one and a quarter rotations.
The engine was running until impact, and the ballistic parachute recovery system was not deployed. Weather conditions are not believed to have been a contributing factor. A witness observing the takeoff from the control tower stated they noticed the canopy was ajar by approximately 5 cm.
Probable Cause
Based on the initial information, the primary suspected cause is an unlatched canopy that opened due to airflow after takeoff. While this does not significantly affect the aircraft’s controllability, it is a major distraction and source of stress for the pilot. Attempting to close a canopy in flight is virtually impossible due to the aerodynamic forces.
The pilot likely noticed the open canopy during the takeoff phase and, while still in the initial climb, may have diverted his attention from flying the aircraft to try and secure it. This distraction is likely what led to the aircraft touching down on the runway again.
Therefore, the critical factor appears to be the pilot’s attempt to fix the problem immediately at a low altitude, combined with the stress of the situation, rather than the open canopy itself.
The pilot then appeared to stabilize the aircraft in a climb. At approximately 100 metres AGL, he initiated a steep, climbing left turn at low airspeed, presumably to return to the airport. This manoeuvre resulted in an aerodynamic stall and subsequent spin.
Recommended Procedure for an Unsecured Canopy
- Before takeoff: Always check the canopy is secure, not just visually but by applying physical pressure. Use your checklists diligently.
- If the issue is detected on the runway: Abort the takeoff and brake to a stop.
- If it’s too late to abort: Continue with a normal takeoff, focusing entirely on flying the aircraft until a safe altitude is reached.
- Only then, assess the situation, remain calm, and plan a return to land via a standard traffic pattern.
- In case of a loss of control: Deploy the ballistic parachute system immediately.
Key Takeaways
This accident highlights how a seemingly minor issue, such as an unlatched canopy, can lead to tragic consequences if a pilot attempts to resolve it during a critical phase of flight. Thorough pre-flight checks and a disciplined response to in-flight emergencies are fundamental to aviation safety.
Incidents involving unsecured canopies are far from rare. Unfortunately, pilots often fail to report these occurrences through official safety management systems—whether within their own flying clubs or to national authorities like the ÚZPLN. This represents a missed opportunity to share valuable lessons and implement preventative measures before a tragedy occurs.
The lesson from this accident is clear: use checklists diligently, do not hesitate to use safety reporting systems, and in any emergency, always remember the golden rule: fly – navigate – communicate.
We hope the lessons learned from this event will help prevent similar accidents in the future.
