What happened
On the morning of December 7, 1983, at approximately 09:39, a collision occurred on runway 01/19 at Madrid-Barajas Airport involving two commercial aircraft. The first aircraft, an Iberia Boeing 727-256 registered as EC-CFJ, was performing a scheduled takeoff for flight IB350 bound for Rome. During its takeoff roll on runway 01, the aircraft reached its V1 decision speed.
Simultaneously, an Aviaco DC-9-32 with registration EC-CGS, operating flight AO134 toward Santander, was taxiing through the outer taxiway toward the runway 01 holding point. The two aircraft collided on the active runway.
The impact caused the DC-9 to be destroyed by a subsequent fire, resulting in the deaths of all 42 occupants (5 crew and 37 passengers). The Boeing 727 sustained severe damage, losing nearly its entire left wing and the associated main landing gear. After the collision, the aircraft slid approximately 460 meters along the runway, eventually coming to a stop on the left edge of runway 01 facing the opposite direction of its intended takeoff. A fire broke out due to released fuel, leading to 51 fatalities (50 passengers and one cabin crew member) and leaving 34 passengers and 8 crew members as survivors.
Findings
The investigation identified that heavy fog at the airport significantly reduced visibility. The primary factor in the accident was the unauthorized entry of the DC-9 onto runway 01/19 while the Boeing 727 was accelerating for takeoff. Due to the dense fog, the crew of the DC-9 was unable to maintain sufficient visual references to realize they had deviated from their assigned taxi route and had entered the active runway.