Investigation Summary
The approach to Tegucigalpa's Toncontín International Airport is notoriously difficult due to the surrounding mountainous terrain. The published VOR/DME approach for Runway 01 required a specific three-step descent profile starting from 7,500 feet MSL. Investigators found that the crew of Flight 414 ignored these mandatory step-downs. Instead, they began a steady, continuous descent from 7,600 feet while still 11 nautical miles away from the airport. This premature descent led the Boeing 727 directly into the side of Cerro de Hula at an elevation of 4,800 feet, which was 800 feet below the mountain's summit. Although the aircraft was equipped with a Ground Proximity Warning System (GPWS), it had been disconnected because Honduran regulations at the time did not mandate its use. The aircraft struck the mountain in a nose-high, approach configuration, which allowed the cockpit and first-class sections to remain relatively intact, accounting for the 15 survivors, including all three flight crew members.
Final Conclusions
The primary cause of the accident was the flight crew's failure to follow the published instrument approach procedure, specifically the required step-down altitudes. Contributing factors included the crew's poor situational awareness and the lack of a functioning Ground Proximity Warning System (GPWS), which had been intentionally deactivated. The high terrain and poor visibility at the time of the approach further reduced the margin for error.
Photographic Evidence (1)
Video Analysis
No video analysis linked for this case file yet.
Systems & Failure Modes
GPWS
Ground Proximity Warning System; it was disconnected at the time of the accident and could have alerted the crew to the rising terrain.
VOR/DME
VHF Omnidirectional Range and Distance Measuring Equipment; the primary navigation aids used for the instrument approach into Toncontín.
Interesting Facts
- 01The aircraft was leased from Continental Airlines and had been in service since 1968.
- 02All three flight crew members survived the initial impact and subsequent fire.
- 03The Ground Proximity Warning System (GPWS) was installed but had been disconnected prior to the flight.
- 04Five passengers who initially survived the crash died before rescue teams could reach them due to weather delays.
- 05The crash site was located 4.8 nautical miles from the runway threshold.
Safety Actions & Advisories
GPWS Mandates
Following the accident, Honduras and other Central American nations moved to mandate the use of functional Ground Proximity Warning Systems on all commercial transport aircraft.
Approach Procedure Review
The VOR/DME approach to Toncontín Runway 01 was reviewed to emphasize the critical nature of the step-down altitudes due to the surrounding terrain.