What happened
On 17 March 2017, at Lyon Saint-Exupéry airport, a serious incident occurred involving a Bombardier CRJ700, registered F-GRZL, and an Airbus A319-111, registered G-EZAZ. The aircraft were operating commercial passenger flights under good meteorological conditions.
During a period of heavy inbound traffic, the controller cleared the F-GRZL to land on runway 35R. Shortly after, the G-EZAZ was cleared to line up and wait on runway 35L, and subsequently cleared for takeoff. While the G-EZAZ was in its high-speed takeoff phase, the controller issued a clearance to the F-GRZL to cross runway 35L.
The crew of the F-GRZL noticed the G-EZAZ accelerating on the parallel runway and applied brakes, coming to a halt before the CAT III runway-holding position. The G-EZA passed in front of the F-GRZL at a speed near V1. The conflict was identified by the controller during a subsequent visual scan, and the crossing aircraft was ordered to hold its position.
The investigation
The BEA examined radio and radar recordings, pilot reports, and the controller's statement. The investigation focused on the controller's management of the strip board and the use of visual scans. The investigators also reviewed the use of different languages (French and English) during radio communications and the effectiveness of the airport's existing surveillance tools, such as the ground radar and stop bar systems, which are primarily active during Low Visibility Procedures (LVP).
Findings
- The primary cause was a conflicting clearance issued by the air traffic controller.
- The controller's task of managing aircraft strips involved overlaying the strip for F-GRZL onto the strip for G-EZAZ, which masked the fact that the runway was occupied.
- High traffic density and repetitive clearance patterns led to the controller performing tasks in an automatic manner, reducing situational awareness.
- The use of different languages for the two aircraft—French for the F-GRZL and English for the G-EZAZ—reduced the ability of the G-EZAZ crew to understand the crossing clearance and detect the conflict.
- The F-GRZL crew's decision to check the runway visually before crossing, a practice informed by their familiarity with the airport, prevented the incursion.
- The airport's ground radar was not being utilized because meteorological conditions were good, and the stop bar system was not active as the airport was outside LVP conditions.
Safety action
- The BEA recommended that the DSNA implement improved work tools and methods to better indicate runway occupancy and prevent conflicting clearances.
- The BEA recommended that the DSNA and the airport management implement alert systems and runway protection tools to increase conflict detection capabilities, even when operating outside of LVP conditions.