What happened
On April 7, 2012, a Cessna 172, registration F-BURV, was conducting a training flight between Pontoise and Mortagne. After approximately one hour of flight, a student pilot landed on runway 07 at Mortagne aerodrome. While taxiing via the central taxiway to reach the parking area, the instructor directed the student to use an alternative taxiway to the right to avoid an aircraft parked on the apron.
As the aircraft proceeded along this path, the instructor realized too late that the right wing was on a collision course with a refueling station. Despite attempts to stop the aircraft, the right wing struck the station. Following the impact, the crew observed a crack on the wing tip and a dent on the leading edge. Using adhesive tape provided by a local aero club, the crew proceeded to perform the return flight with a different student pilot, believing the aircraft was still airworthy.
The investigation
Investigators examined the aircraft and found that the damage was much more severe than initially perceived; a mechanical inspection revealed significant damage to the rear spar of the right wing. The investigation also looked into the taxiway configuration and the crew's decision-making process.
It was noted that the student pilot had primarily trained on a Cessna 150, which has a smaller wingspan than the Cessna 172. Furthermore, the instructor was preoccupied with personal family matters at the time, which influenced the decision to provide instructions while taxiing to save time, rather than waiting for the parked aircraft to move. The investigation also found that a complete pre-flight inspection was not performed after the collision, and no qualified mechanic was present to assess the structural integrity of the wing.
Regarding the aerodrome, the distance between the center of the taxiway used and the refueling station was only 5 meters, which is less than the aircraft's semi-wingspan. The taxiway lacked centerline markings, and the refueling station was not noted on the Visual Approach Chart (VAC). A subsequent safety inspection by the regulatory authority determined that this specific path should not be classified as a taxiway due to its proximity to the central taxiway.
Findings
- The primary cause of the collision was the late detection of the insufficient clearance between the aircraft and the refueling station.
- The instructor's attention was focused on delivering instructions to the student, which diverted attention from external monitoring.
- A lack of airfield signage and missing information on the VAC regarding the path through the refueling area contributed to the error.
- Personal preoccupations led the instructor to make decisions aimed at saving time, such as using the alternative taxiway without waiting for the parked aircraft to clear the path and failing to conduct a thorough post-collision inspection.
- The decision to continue flying with the aircraft based only on visible surface damage, without professional mechanical assessment, compromised flight safety.
Safety action
- The aero club distributed a safety feedback report to its members regarding the dangers of operating an aircraft with known damage.
- The regulatory authority included a corrective action in its action plan concerning the designation and use of the taxiway in question.