What happened
On 11 September 2019, at the Itxassou aerodrome in France, a COMCO IKARUS C42 (identified as 03AEN) was performing a glider tow flight. The microlight was towing a Schleicher ASK21 (registered F-CITS), which carried a student-pilot and an instructor.
During the takeoff roll on runway 26, the microlight began to deviate left of the centerline due to engine torque and wind effects. The instructor in the glider instructed the student to follow the tug's path. Shortly after liftoff, the microlight adopted an increasingly steep nose-up attitude. The instructor attempted to communicate with the tug pilot via radio several times to request a correction, but received no response. The microlight's left wing subsequently stalled, causing the aircraft to crash into the ground. The instructor released the tow cable before the impact, but the glider subsequently struck a tree. The tug pilot was deceased, while the two occupants of the glider were unscathed.
The investigation
The BEA examined the wreckage of both aircraft and reviewed the medical and regulatory history of the pilot. Investigators found that the microlight wreckage was intact and showed no mechanical anomalies. The autopsy of the pilot revealed traumatic injuries from the crash, but also identified evidence of pre-existing heart disease. Medical records showed the pilot held a class 2 medical certificate that included an Operational Safety pilot Limitation (OSL), which required a second qualified pilot to be on board to mitigate the risk of in-flight incapacitation. However, because the flight was conducted in a microlight, current regulations did not mandate this second pilot, allowing the tug pilot to fly alone.
Findings
- The primary cause of the accident was the in-flight incapacitation of the tug pilot, likely due to a medical event (cardiocirculatory failure).
- The pilot's advanced age and the fact that he had performed nine towing flights that afternoon may have contributed to the medical event.
- A regulatory gap allowed a pilot subject to an OSL limitation to perform towing operations alone in a microlight, as the medical requirements for microlight flight do not mandate the presence of a second pilot.
- The pilot's lack of response to radio calls from the glider crew confirmed the loss of control following his incapacitation.