What happened
On May 30, 2008, a B&F Technik Factory FK9 Mark IV ultralight aircraft, identified as 31-GJ, was performing an instructional flight at the Toulouse-Lasbordes airfield. During the third circuit on the unpaved runway 34, the instructor announced a full landing on the traffic pattern's downwind leg and received clearance from the controller. Following the completion of the circuit, the aircraft performed a touch-and-go maneuver.
Witnesses observed the aircraft during its initial climb, noting a high pitch attitude and erratic movements around the roll and yaw axes. The flight appeared unstable, maintaining a low airspeed between 50 and 100 meters of altitude. The aircraft subsequently entered a spin and impacted the ground in a steep, vertical attitude, resulting in a post-crash fire. There were two fatalities involving the instructor and the student.
The investigation
The investigation focused on the aircraft's flight path, the mechanical condition of the airframe, and the pilot's recent training history. Investigators examined the wreckage and found that the rudder control linkage remained intact, though the fire prevented a full assessment of the pitch and roll controls. The engine showed no signs of malfunction prior to the impact, and the aircraft's onboard parachute had not been deployed.
Investigators also reviewed the instructor's recent regulatory history. While the instructor had recently completed a knowledge update course for ULM instruction in May 2008, a previous flight check in a glider earlier that year had resulted in a failure. That check had highlighted significant deficiencies in longitudinal attitude control and flight symmetry, leading to a requirement for full retraining that the instructor had not yet completed.
Findings
- The accident was caused by a loss of control during the initial climb, leading to a spin.
- The loss of control was likely due to an excessive pitch attitude and imprecise flight symmetry.
- The instructor's flying skills appeared to have degraded over time, a decline that was not detected during the recent ground-based knowledge update course.
- The aircraft's flight characteristics during the takeoff—specifically the high pitch and erratic yaw/roll—were consistent with a condition prone to an asymmetric stall.