What happened
A flight operated by Aviaco, flying a Heron, departed from Zaragoza at 19:19 local time, bound for Barcelona. During the approach, at approximately 20:06 local time, the crew requested visibility information while navigating a wide base leg. At this same time, another aircraft, registration EC-AEJ, was positioned at Barcelona and awaiting departure, though it had previously been denied takeoff clearance.
Once the Aviaco flight reported being five minutes from the airport, the aircraft with registration EC-AEJ was granted permission to take off. Shortly after this clearance, both aircraft were operating at an altitude of approximately 150 meters on paths that intersected. To avoid a collision, the pilot of the Heron attempted an abrupt evasive maneuver. This sudden movement caused the aircraft to lose control, leading to a crash into the sea off the coast of Castelldefels. The accident resulted in 16 fatalities, with no survivors reported.
Findings
The investigation determined that the primary factor was the decision to permit the takeoff of EC-AEJ without having confirmed the precise position of the incoming Heron. This lack of situational awareness regarding the arrival's exact location led to the intersecting flight paths and the subsequent loss of control during the emergency avoidance maneuver.