What happened
On August 6, 2015, a Diamond DA40NG was performing a landing on runway 06 at the Żerniki airfield. The aircraft touched down approximately 300 meters from the end of the runway, which was roughly the midpoint of the available runway length. Despite the pilot immediately initiating braking procedures and retracting the flaps to increase braking effectiveness, the aircraft could not stop in time. The aircraft overran the runway, coming to a halt 10 meters beyond the end of the paved surface. The impact caused a fracture to the nose landing gear strut and significant damage to the propeller.
The investigation
The investigation examined the landing performance, environmental conditions, and the pilot's approach parameters. The inquiry focused on the relationship between the approach speed, the aircraft's weight, and the specific atmospheric conditions present at the time of the incident. The investigation also reviewed the airfield's landing performance documentation (IUwL) regarding recommended speeds and required landing distances.
Findings
- The primary cause of the accident was an error in planning the landing approach under conditions of weak, variable wind, which led to the aircraft touching down 300 meters short of the runway end.
- The pilot conducted the approach at a speed of 85 knots, which was higher than the 77 knots recommended in the airfield's landing performance documentation. The documentation specifically notes that higher approach speeds result in significantly longer landing distances during the flare.
- High density altitude contributed to the increased landing distance; while the airfield's actual elevation is 82 meters, the density altitude was 817 meters due to an ambient temperature of 35°C.
- The aircraft was operating at a weight near its Maximum Takeoff Weight (MTOW) on a runway with a total length of 618 meters. According to the airfield documentation, the standard landing distance from an obstacle for this aircraft at MTOW is 639 meters, with a subsequent rollout of 310 meters.