What happened
On January 8, 2006, at approximately 15:00, a Robin DR 400-120, registered F-GBUM, was performing instructional circuit patterns at the Valréas aerodrome. The flight crew consisted of an instructor and a student pilot. During the flight, the instructor arranged a formation flight with another aircraft, a Jodel registered F-PPPD, which was also operating in the circuit.
The instructor directed the student to position the Robin DR 400-120 slightly lower and approximately five meters behind the right side of the Jodel's tail. During the final approach, the instructor took control of the aircraft. While the Jodel pilot chose a shallow descent angle to land offset from the threshold, the instructor failed to notice that the Jodel's trajectory was low. Consequently, the Robin DR 400-120 struck the ground approximately thirty meters before the start of the runway threshold. During the subsequent taxiing, the aircraft's nose and main landing gear collapsed as it crossed a roadside verge. Although the instructor applied full power and the aircraft briefly regained altitude, the instructor decided to land further down the runway, where the aircraft slid for about 300 meters before coming to a halt.
The investigation
The investigation focused on the flight dynamics during the formation maneuver and the physiological state of the instructor. The investigators examined the flight paths of both aircraft and the communication between the crews. Additionally, post-accident breathalyzer tests were conducted on the instructor to determine the impact of alcohol consumption on flight performance.
Findings
- The primary cause of the accident was the landing before the runway threshold during the formation maneuver.
- The instructor's attention was overly focused on maintaining a constant distance from the lead aircraft, leading to a loss of situational awareness regarding the altitude of the Jodel.
- The instructor's judgment and reaction times were impaired by the consumption of alcohol during lunch approximately two hours prior to the flight. Breathalyzer tests revealed blood alcohol levels of 0.36 mg/L and 0.31 mg/L of expired air during the post-accident period.
- There was an element of overconfidence during the execution of the formation maneuver.