An Iberia Airbus A321XLR and an Air Europa Boeing 787-9 narrowly avoided a mid-air collision on the night of July 10th. The two aircraft were flying in opposite directions on the same flight path, at the same altitude, when their collision avoidance systems initiated opposing emergency maneuvers. Both aircraft were able to continue their journeys and land normally.
Two transatlantic flights on a conflicting trajectory
The incident occurred at approximately 1:22 UTC over the Atlantic Ocean, off the coast of Western Sahara, in airspace managed from the Canary Islands. The two aircraft were flying at flight level FL360, approximately 36,000 feet or 11,000 meters altitude.
The first aircraft was the Airbus A321XLR registered EC-OLE, operating Iberia flight IB140 between Recife, Brazil, and Madrid. Approaching it was the Air Europa Boeing 787-9 Dreamliner EC-ODH, operating flight UX57 between Madrid and São Paulo. Both aircraft were following the same oceanic route in opposite directions while maintaining the same altitude.
Both crews had been cleared to maintain FL360. The cause of this loss of separation has not yet been established. Therefore, at this stage, nothing allows us to formally attribute the incident to an error by a controller or pilot, a coordination problem, or a faulty transmission of instructions.
A first warning before the avoidance order
When the flight paths became dangerously convergent, the TCAS system installed on board both aircraft detected the risk. A first traffic alert, called Traffic Advisory, warned the crews of the presence of another aircraft nearby. The system then triggered a Resolution AdvisoryThis means an evasive action to be executed immediately. These orders are automatically coordinated between the aircraft involved to prevent the two pilots from performing the same maneuver. One pilot is thus ordered to climb while the other is instructed to descend.
The Airbus descends, the Boeing ascends
In the cockpit of the Iberia Airbus, the TCAS requested a descent. The A321XLR lost approximately 500 feet and settled around FL355, or approximately 35,500 feet. At the same time, the Air Europa Boeing 787 received the opposite instruction. The aircraft gained approximately 400 feet, reaching nearly 36,400 feet. The crews immediately executed the instructions, creating sufficient vertical separation between the two aircraft. Once the flight paths were separated, the message Clear of Conflict The situation in the cockpits was declared over. The Airbus and Boeing aircraft then resumed their flight profiles and continued on to Madrid and São Paulo. No injuries or damage were reported.
An independent air traffic control system
TCAS operates on board the aircraft independently of instructions given by air traffic controllers. It monitors the transponders of surrounding aircraft, analyzes their altitude and changes in altitude, and then calculates the risk of a close approach. Upon receiving an alert, pilots must immediately follow the indicated vertical maneuver, even if it temporarily contradicts air traffic control clearance. The crew then informs the controller of the deviation performed.
An investigation to understand the loss of separation
The Spanish Civil Aviation Accident and Incident Investigation Commission (CIAIAC) has opened an investigation. It will examine, among other things, the authorizations issued to the two aircraft, radio communications, flight data, and recordings related to the TCAS activation. The key issue is how two aircraft flying in opposite directions could have ended up on the same axis and at the same altitude over the Atlantic. Until the investigation's conclusions are published, the widely circulated claim of "human error" remains premature. The only established fact is that the coordinated TCAS commands and the immediate reaction of both crews prevented the conflict from escalating into a collision.
