What happened
On June 14, 2014, a Cessna TU206G seaplane, registration N5411Z, was conducting water landing practice on Lake Vättern, Sweden. Following a landing near Visingsö, the crew encountered rough sea conditions with waves reaching up to 1.5 meters. Due to the weather, the pilots decided to cease flying operations and prepared to drift toward the island of Visingsö.
To facilitate drifting backward toward land, the engine was shut off. However, the aircraft's water rudders had been left in the downward position. This configuration caused the aircraft to catch the wind, turn sideways across the waves, and eventually capsize. Both the commander and the co-pilot managed to exit the overturned aircraft. While the co-pilot was able to swim to shore and eventually alert emergency services, the commander tragically succumbed to drowning.
The investigation
The Swedish Accident Investigation Authority (SHK) examined the mechanical state of the aircraft, the weather conditions, and the rescue operation. The investigation revealed that the aircraft lacked a specific placard instructing pilots to keep the water rudders up during water taxiing.
Investigators also scrutinized the rescue efforts. The alert to emergency services was delayed by over two hours because the co-pilot had to swim to land to find a telephone. Furthermore, the SHK noted that the rescue operation was terminated by the JRCC after approximately 4.5 hours, despite survival models suggesting a much longer window of possibility. The investigation also highlighted that the commander's life vest was a dark blue sailing type, which made him extremely difficult to spot against the water.
Findings
- The primary cause of the accident was the water rudders remaining lowered after the engine was shut off, which allowed the wind to turn the aircraft broadside to the waves.
- The aircraft lacked a warning placard regarding the required position of the water rudders.
- The commander's dark blue life vest lacked high visibility and was difficult to locate in the lake.
- There were delays in both the initial emergency notification and the conclusion of the air rescue search.