What happened
On May 21, 2014, a Cessna 150, registration EC-CPT, operated by Panamedia, was performing a solo instructional navigation flight originating from Son Bonet aerodrome. During the return leg, the student pilot became disoriented and failed to verify the heading of the directional gyro against the magnetic compass. Consequently, the aircraft maintained a southbound course from point E, inadvertently entering the Palma de Mallorca airport Control Zone (CTR) without authorization or communication with air traffic services.
Simultiously, an EasyJet A319, registration G-EZDM, was established on the ILS approach for runway 24L at Palma de Mallorca. The crew received a TCAS Traffic Advisory (TA) without altitude information. Upon visual confirmation of a light aircraft positioned slightly above and following their direction, the crew elected to continue the approach rather than execute a missed approach, maintaining visual contact with the intruder. The separation between the two aircraft reduced to a horizontal distance of 0.1 NM.
The student pilot eventually realized the error upon seeing the airport runways and initiated a right turn to exit the CTR. During this maneuver, the pilot observed the approaching A319 and began climbing to ensure separation before returning to Son Bonet to land.
The investigation
The CIAIAC investigation examined the flight paths of both aircraft, which were validated via radar tracks. The investigation established that the Cessna 150 was operating with a transponder in Mode A, which does not transmit altitude information, preventing the A319's TCAS from providing a resolution advisory (RA).
Investigators also reviewed the tower controller's actions. The controller was unaware of the light aircraft's presence until notified by the EasyJet crew. While the tower controller attempted to contact the student pilot on the emergency frequency (121.5 MHz) without success, the investigation noted that the approach controller may have observed the proximity of the two aircraft on radar but failed to alert the tower controller.
Findings
- The primary cause of the incident was a navigational error by the student pilot, which led to the unauthorized entry into the Palma de Mallorca CTR.
- A significant contributing factor was the pilot's reliance on the directional gyro without having properly calibrated the instrument with the magnetic compass prior to takeoff or during the flight.
- The student pilot failed to utilize identifiable ground references, such as the nearby highway, to maintain correct positioning.
- The lack of altitude information from the Cessna 150's Mode A transponder limited the effectiveness of the A319's TCAS alert.