What happened
On 0나 January 2022, at Son Bonet Aerodrome in Mallorca, Spain, a near-collision occurred between a ROBINSON R 4-4 CLIPPER I helicopter, registration EC-MTH, and a MOONEY M 20K 231 aircraft, registration D-EKUR.
The helicopter, operated by a flight school, was conducting a local instruction flight. After completing several circuits, the helicopter approached the threshold of runway 23 and entered a low-altitude hover over a grassy area just to the right of the runway. The crew, consisting of an instructor, a student, and a passenger, remained in this stationary hover for approximately 45 seconds while attempting to stabilize the aircraft.
Simultally, the MOONEY M 20K 231 was performing a direct final approach to land on runway 23. As the aircraft reached the threshold and was nearly at touchdown, it passed extremely close to the hovering helicopter. At the moment of closest approach, the horizontal separation between the two aircraft was approximately 4 meters. To avoid a collision, the helicopter pilot performed an evasive maneuver, climbing slightly and turning to the right. The aircraft continued its landing roll and exited the runway via taxiway S3.
The investigation
The CIAIAC investigation utilized airport camera footage, radar traces, and witness testimony to reconstruct the event. The investigation examined the radio communications, which were not recorded, but noted that the helicopter crew had reported their position on the radio, though the aircraft crew did not hear them. A witness on the ground confirmed seeing the helicopter hovering near the threshold and the aircraft approaching on short final.
Findings
- The helicopter crew failed to follow established aerodrome procedures; instead of proceeding to the designated exit taxiway S2 to land or take off, the aircraft remained hovering near the runway threshold.
- The failure to adhere to landing procedures by both crews was the primary cause of the loss of separation.
- The helicopter's position, with its tail toward the runway head, obstructed the crew's view of approaching traffic.
- The aircraft pilot failed to initiate a go-around despite the presence of the helicopter, though the investigation noted that an immediate climb by the aircraft might have actually decreased vertical separation.
- A crosswind was present at the time, which may have pushed the helicopter toward the runway centerline.