Incident Overview
On 6 October 2015, at approximately 18:13 UTC, an air proximity incident occurred in the controlled airspace of Szczecin-Goleniów Airport (TMA EPSC). The aircraft involved were a Saab 340 (SF34) departing from EPSC to EPWA (Warsaw Chopin Airport) and a Dash 8 (DH8D) approaching the CHO NDB from the south. The weather conditions were CAVOK (ceiling above 1500 meters, visibility at least 10 km) and the time of day was night.
Sequence of Events
The SF34 crew received clearance for departure from Runway 13 with an initial climb to 6000 ft, turning left to the CHO waypoint. The aircraft took off at 18:13 UTC. Meanwhile, the DH8D crew had been cleared to descend to 7000 ft (QNH 1013 hPa). The controller informed the DH8D crew of traffic on a reciprocal course (the SF34 climbing to 6000 ft) and instructed them to report visual contact. The DH8D crew acknowledged and immediately reported seeing the SF34. Similarly, the SF34 crew was advised of the DH8D descending to 7000 ft and confirmed visual contact. Both crews were asked to report passing.
At about 18:13 UTC, the SF34 crew asked if they could deviate from course to ensure safe passing. The controller immediately asked if they were maintaining 6000 ft; the SF34 crew replied that they had already passed the transition altitude. The controller repeated the instruction to maintain 6000 ft. Meanwhile, the DH8D crew called the SF34 crew several times, instructing them to descend, and then on their own initiative began a course change to avoid collision. The DH8D crew reported the new course to the controller and subsequently performed a procedural approach from the OL point. The Traffic Collision Avoidance System (TCAS) did not generate any warning.
Analysis of the SF34 Climb
According to radar data from the PEGASUS 21 system, the vertical separation during the event was 500 ft. The SF34 crew stated that after takeoff from Runway 13, at 1000 ft they turned left toward CHO and continued climbing to 6000 ft on QNH 1013 hPa. At 5000 ft, the altitude alert system indicated 1000 ft remaining to the target altitude. When the aircraft passed the assigned altitude and did not stop climbing, the crew disengaged the autopilot (AP) and switched to manual control, transitioning to level flight and then to descent. The delay in reaction and aircraft inertia caused the aircraft to reach 6500 ft before descending, while also deviating laterally due to the opposing traffic. The TCAS Resolution Advisory (RA) did not activate. The SF34 crew observed the DH8D on the opposite course.
After passing the CHO point and the DH8D, the SF34 crew received clearance from the controller to continue climbing to FL 190, routing to EPWA. The subsequent climb proceeded normally with autopilot engaged, and the altitude alert activated as expected. However, the crew reported that after passing FL 190, the aircraft again failed to capture the selected altitude, prompting a second manual intervention. After landing at EPWA, the captain of the SF34 reported the anomaly to maintenance and made an appropriate logbook entry.
Crew Information
The SF34 crew consisted of a captain (male, 58 years old, total flying time 7200 hours, 3500 on type) and a first officer (male, 55, 4830 hours total, 3022 on type). Both had valid licenses and medical certificates. Their rest periods were adequate per regulations.
The DH8D crew comprised a captain (male, 49, 14000 hours total, 1500 on type) and a first officer (male, 30, 1370 hours total, 670 on type). They also held valid credentials and had sufficient rest.
Aircraft Information
Both aircraft had valid certificates of registration and airworthiness.
Probable Cause
Violation of the air traffic control clearance and failure to level off at the assigned altitude, leading to a loss of separation minimum and a dangerous proximity.
Safety Recommendations
The investigation committee did not issue any safety recommendations.