Investigation Summary
The approach was conducted in darkness and ground fog. Runway 23L was closed for resurfacing, a fact noted in NOTAMs and communicated by ATC. The crew was cleared for a sidestep approach: they were to use the ILS for 23L (which had the equipment) but transition visually to land on 23R. The CVR revealed confusion in the cockpit; the captain realized they were on the wrong path too late, exclaiming, 'No, this is the approach to the goddamn left.' The aircraft touched down with its left gear in the grass and right gear on the shoulder of 23L. As the crew attempted a go-around, the right main gear struck a truck loaded with 10 tons of earth, which tore off the gear and damaged the tailplane. The crippled DC-10 remained airborne briefly before striking an excavator and eventually crashing into a maintenance hangar and a terminal building. The impact with the terminal caused a massive fire and resulted in additional injuries to several people inside the building.
Final Conclusions
The Mexican Directorate General of Civil Aviation concluded the probable cause was the crew's failure to comply with the authorized landing minimums and the sidestep procedure. The pilots continued the descent into a closed runway without having the runway environment in sight, violating operational procedures. Contributing factors included the low visibility (fog) and the crew's failure to execute a missed approach at the decision height of 600 feet.
Video Analysis
No video analysis linked for this case file yet.
Systems & Failure Modes
Instrument Landing System (ILS)
The crew used the ILS for the closed Runway 23L to guide their approach, intending to sidestep to 23R, but failed to transition.
Cockpit Voice Recorder (CVR)
Captured the captain's realization of the runway error seconds before the initial impact.
Interesting Facts
- 01The accident resulted in 72 fatalities on board and 1 fatality on the ground (the truck driver).
- 02Of the 88 souls on board, 16 survived the crash.
- 03Runway 23 Left had been closed for resurfacing since October 19, 1979.
- 04The impact with the dump truck was so severe it removed the right landing gear leg and part of the tailplane.
- 05The aircraft involved, N903WA, was nicknamed 'Night Owl' by Western Airlines.
- 06This remains the deadliest aviation accident in the history of Mexico City.
Safety Actions & Advisories
Sidestep Procedure Review
The accident highlighted the dangers of sidestep approaches in low visibility, leading to stricter requirements for maintaining visual contact with the landing runway before descending below decision height.