Serious Incident to the Bombardier CRJ700 registered F-GRZL and to the Airbus A319-111 registered G-EZAZ on 17/03/2017 at Lyon Saint-Exupéry (69)

 The CRJ700, registered F-GRZL, call sign HOP83AJ, was carrying out a commercial air transport (passenger) flight between Biarritz Pays Basque airport (Pyrénées-Atlantiques) and Lyon Saint-Exupéry airport (Rhône). The A319, registered G-EZAZ, call sign EZY748Z, was carrying out a commercial air transport (passenger) flight between Lyon Saint-Exupéry and Nantes Atlantique (Loire-Atlantique). 

Runways 35L and 35R were in use and managed as a nominal twin runway. The meteorological conditions were CAVOK.

The LOC controller, in position for less than an hour, had principally dealt with inbound aircraft. The majority of the time, he had cleared them to cross runway 35L as soon as they had vacated runway 35R, without there being a potential conflict, due to there being no departures. 

The controller cleared the EZY748Z flight to take off from runway 35L and then gave a crossing clearance to the HOP83AJ flight without detecting the conflict. During the out-of-window scan, probably carried out partially, he did not see the aeroplane taking off and was not alerted when overlaying the strips in the bay dedicated to the runway. 

The rhythm imposed by the density of the traffic, and the repetition of the same clearances, in particular during the inbound hub, inevitably led to the controller carrying out the various tasks somewhat automatically (management of strips, clearances, out-of-window scan). The detection of a conflicting clearance can then fail, particularly as the strip board, used in the conditions laid down at Lyon Saint-Exupéry, does not constitute a robust barrier. The distinction between an aeroplane lined up and an aeroplane cleared to take-off is solely based on the runway number being ringed or simply underlined. This difference is barely noticeable when quickly handling the strips. Overlaying the strips in these situations leads to the masking of an aircraft which might be conflictual.

When the crew of the EZY748Z flight were cleared to take-off, the crew of the HOP83AJ flight were flying over the threshold of runway 35R. The EZY748Z crew did not understand the crossing clearance given to the HOP83AJ crew as it was given in French. In the similar occurrence at the same aerodrome a year earlier, the crew were listening on the frequency to the clearances given in English which permitted the detection of the conflict. The use of several languages in exchanges with crews may reduce the situational awareness of the crews in the surrounding traffic with the possibility of recovery becoming more uncertain. 

The HOP83AJ crew saw EZY748Z taking off when they visually checked the runway before crossing it. The fact that the HOP83AJ crew were based at Lyon and were aware of the runway incursion risk probably contributed to them actively checking the runway before crossing it. Simultaneously, the controller detected the conflict when he carried out the out-of-window scan again. This prevented the runway incursion from occurring. The HOP83AJ aeroplane came to a halt before the CAT III holding position, i.e. 60 m before the CAT I holding position marking the entry onto the runway outside LVP conditions.