What happened
On May 7, 2019, at 10:56 UTC, a potential runway conflict occurred at Treviso Sant’Angelo Airport involving two Boeing 737-800 aircraft, registrations EI-DPH (operating flight RYR706) and EI-EFN (operating flight RYR1279).
At the time of the event, the crew of RYR706 was holding at runway centerline position 'A' for runway 25, awaiting departure. Simultaneously, RYR1279 was on short final for the opposite runway, 07, having been cleared to land by the tower approximately three minutes prior.
The air traffic controller (ATC) at the Tower position issued a takeoff clearance to RYR706 for runway 25. However, the crew of the departing aircraft noticed the approach lights of the arriving aircraft on the opposite runway and requested confirmation of their clearance. The crew of RYR127 and the tower controller then realized the conflict, and the controller immediately instructed RYR706 to hold short of runway position 'A'. The arrival of RYR127 proceeded without further incident, and RYR706 departed once the runway had been vacated.
The investigation
The ANSV investigation examined the operational procedures and equipment at the Treviso Tower. The investigation found that the Tower position manages both ground movements and aircraft in flight, but lacks specialized equipment to monitor traffic outside its immediate visual range.
At Treviso, takeoff and landing operations typically use opposite runways (25 and 07), requiring aircraft to backtrack. The investigation revealed that the Tower controller was coordinating with the Coordination (COO) position, which in turn was coordinating with the Approach (APP) control. The controller's attention was diverted by the receipt of a departure release from the APP, which the controller misinterpreted as a signal that the runway was clear for takeoff, momentarily forgetting the aircraft already cleared to land on the opposite runway.
Findings
- The primary cause was human and organizational factors, specifically a temporary loss of situational awareness by the tower controller.
- The controller's interpretation of the departure release was distorted by the simultaneous management of multiple tasks and the lack of clear distinction between ground movement and runway management roles.
- The Tower lacks radar presentation or monitoring tools to track the position and distance of approaching traffic beyond the controller's visual range.
- There is a lack of clearly defined procedures or tools to provide unambiguous evidence of which specific aircraft is authorized to occupy the runway at any given time.
Safety action
The ANSV issued safety recommendations to ENAC, urging ENAV SpA to consider equipping the Tower with radar presentation repeaters to improve situational awareness. Additionally, the agency recommended developing more robust internal procedures to clearly identify the single authorized user of the runway and ensuring that operational practices at ATS facilities strictly adhere to approved regulatory standards.