History of the Flight
The solo student pilot took off from runway 10 to perform runway circuits with the authorization of the club’s instructor. In the left-hand downwind leg, he configured the aeroplane with flaps set to the take-off position. On final approach, after correcting the approach slope at an estimated altitude of 700 ft, the pilot reported the aeroplane was stabilized with a speed of 140 km/h. The wind reported by the controller was 140° at 11 kt. At wheel touchdown, centred on the runway axis with reduced power, the pilot felt normal contact with the runway. He added that the aeroplane bounced. On making contact with the runway again, the nose landing gear bent under the fuselage and then the main landing gear failed, piercing the wings. The aeroplane slid and came to a halt on the runway approximately 300 m from the touchdown zone markings of runway 10.
Additional Information
Pilot Information
The student pilot had logged 74 flight hours, of which 9 in the previous 30 days. He started introductory flights in February 2013 and training in April 2014. He intended to sit the practical flight test of the Basic Pilot Licence for aeroplanes before the end of his theoretical examination validity for the Private Pilot Licence, which expired on 7 April 2016. He needed about 40 more minutes of solo flight time. The pilot chose to land with flaps set to the take-off position due to wind and turbulence conditions. He noted an increase in wind strength and crosswind component forecast. He found it difficult to estimate the bounce amplitude and height but considered it a small bounce with normal contact. He had never bounced during training and was not prepared to abort the landing. He described the flare as a personal perception without formal reference frame, especially on runway 10 with an upward slope.
Aerodrome Information
Rennes Saint-Jacques aerodrome has two paved runways and one grass runway. Runway 10/28 is 2,100 m long and 45 m wide, with a landing distance available of 2,030 m due to a displaced threshold. A PAPI with a 3.0° approach slope is on the left side. Runway 10 has an upward slope; after the touchdown zone markings, the average slope is approximately 1.6% over 500 m.
Meteorological Information
Wind recorded at 11:05 was 110-140° at 10 kt, maximum 14 kt. The TAF forecast rain showers between 11:00 and 14:00. At 11:12, the tower controller reported wind 130° at 10 kt; at 11:17, wind 140° at 11 kt. Estimated maximum crosswind component during final approach was 7 kt.
Aircraft Information
The Robin DR400-120 has a maximum take-off and landing weight of 900 kg. Take-off speed is 100 km/h. Stall speeds (Vs) with flaps take-off and landing positions are 88 and 83 km/h respectively at maximum weight. The flight manual specifies a final approach speed of 110 km/h for flaps landing position, and 130 km/h plus half gust speed for crosswind or strong wind with flaps take-off position. Standard approach speeds (1.3 Vs) without wind correction are 115 km/h for flaps take-off and 108 km/h for flaps landing.
Flare Information
During the period 2009-2019, accidents in the landing phase represent half of all accidents to aeroplanes with MTOW under 2.25 t in France. The flare involves rapid changes in slope, pitch attitude, and speed. Visual references are crucial and depend on the touchdown point, aircraft characteristics, and environment. Landing on an upward sloping runway alters visual references and may require greater nose-up input, modifying pitch attitude and flare duration.
Conclusions
Scenario
The final approach was conducted with flaps take-off and increased speed. The pilot’s speed of 140 km/h was excessive relative to actual wind conditions (max crosswind 7 kt, headwind 9 kt). While excessive speed contributed to the bounce, starting the flare too high due to different visual references from the upward sloping runway may also have been a cause. After the bounce, the pilot may have made nose-down inputs to land, or possibly the aeroplane stalled. The subsequent contact of the nose and main landing gear exceeded structural limits, leading to collapse.
Contributing Factors
- Management of the final approach in the presence of apprehension linked to wind forecasts, in a flight context with time pressure to take the practical test.
- Excessive increase in speed on final approach.
- Management of the flare, which depends on numerous factors.