27 fatalities

1969-09-21: Boeing 727-100 (XA-SEJ) — Mexicana de Aviación — Mexico City-Benito Juarez, Mexico

Mexico City-Benito Juarez, MexicoLanding (descent or approach)

On September 21, 1969, a Boeing 727-100 (registration XA-SEJ) operated by Mexicana de Aviación was involved in an aviation accident near Mexico City-Benito Juarez, Mexico during landing or approach. 27 people were killed. Investigators recorded the probable cause as: The aircraft was operated in an unairworthy condition due to maintenance technicians failing to follow proper procedures for installing the Flight Data Recorder and Cockpit Voice Recorder. This summary draws on records from the Bureau of Aircraft Accidents Archives (B3A); 15 related events involving the same aircraft type or operator are linked below.

Sourcesthe Bureau of Aircraft Accidents Archives (B3A)Primary reportUpdated 1781237122Data APIEditorial standards
Boeing 727-100
Photo: Pete Macklin / CC BY-SA 2.0, via Wikimedia Commons

A three-engine aircraft crashed short of the runway threshold at Mexico City-Benito Juárez Airport, resulting in 27 fatalities and 80 injuries.

What happened

During the final approach to runway 23L at Mexico City-Benito Juárez Airport, a three-engine airplane experienced a loss of altitude. The aircraft impacted the ground approximately 1.5 km before reaching the runway threshold. Following this initial impact, the plane bounced and briefly regained flight before the nose gear and forward section of the fuselage collided with a railway embankment.

Following the collision with the embankment, the aircraft lost control and crashed near the runway threshold, where it broke into multiple fragments. The accident resulted in 27 fatalities, including five crew members and 22 passengers. Additionally, 80 people were injured during the event, while 15 others remained unharmed. The aircraft was completely destroyed.

Findings

Investigations into the crash highlighted significant maintenance failures that rendered the aircraft unairworthy. It was determined that technicians responsible for the aircraft's upkeep failed to adhere to established procedures. Specifically, the Flight Data Recorder (FDR) was not correctly installed and was in an unserviceable state at the time of the accident. Furthermore, the Cockpit Voice Recorder (CVR) was missing from the aircraft because maintenance personnel had neglected to reinstall it prior to the flight.

Probable cause

The aircraft was operated in an unairworthy condition due to maintenance technicians failing to follow proper procedures for installing the Flight Data Recorder and Cockpit Voice Recorder.