Investigation Summary
The investigation revealed a significant breakdown in cockpit discipline driven by time pressure. The pilots had lost track of time while having coffee in the terminal and returned to find the aircraft already boarded. In their haste to depart before the airport's night-flight curfew and to avoid waiting for an approaching Avior Airlines flight, they skipped mandatory pre-flight checklists. A critical requirement for the ATR 42 is a 180-second stationary period after powering on the Attitude and Heading Reference System (AHRS) to allow the gyroscopes to align. The crew initiated taxiing only 2 minutes and 40 seconds after startup and began the takeoff roll at approximately 152 seconds (2 minutes and 32 seconds) after the system was powered, meaning the system was not yet operational. The captain reportedly believed he could handle the departure without the system, having done so once before. However, once in the clouds, the lack of instruments led to spatial disorientation. The crew attempted to determine their position using a small GPS display and an unreliable magnetic compass but inadvertently flew toward the 'Indian Face' rock wall. While the basic GPWS may have provided a late aural alert, the Enhanced Ground Proximity Warning System (EGPWS) functions were inoperative because they required data from the failed AHRS/EFIS systems, depriving the crew of early visual terrain warnings.
Final Conclusions
The primary cause was the crew's failure to follow mandatory pre-flight procedures and checklists, specifically the failure to allow the AHRS to initialize. Contributing factors included extreme time pressure, overconfidence of the captain, and the use of an unauthorized departure route in a high-risk mountainous environment.
Photographic Evidence (1)
Video Analysis
Unraveling the 28 Seconds that Sealed the Tragic Destiny of SBA 518 — A detailed look at the crash of Santa Bárbara Airlines Flight 518, where a rushed departure led to a fatal navigation failure in the Andes.
If playback is blocked, the owner has disabled embedding — use the link above.
Airframe & Maintenance
Crew Experience
Captain
Aldino Garanito Gómez, age 36.
First Officer
Denis Ferreira Quintal, age 29.
Systems & Failure Modes
AHRS
Attitude and Heading Reference System; provides flight instruments with data on the aircraft's pitch, roll, and heading.
GPWS
Ground Proximity Warning System; designed to alert pilots if the aircraft is in immediate danger of flying into the ground or an obstacle.
Interesting Facts
- 01The aircraft was 22 years old at the time of the accident.
- 02The AHRS requires 180 seconds of stationary time to synchronize; the crew took off 28 seconds before this was complete.
- 03Mérida's airport is surrounded by high terrain, and night flights were prohibited due to the lack of lighting and safety margins.
- 04The impact was so severe that the aircraft was described by rescuers as 'pulverized'.
- 05Commercial service at Mérida was suspended for five years following the accident.
- 06The meteorological station in Merida and the tower's communication recording system were both inoperative at the time of the accident.
Safety Actions & Advisories
Airport Closure and Review
Commercial operations at Alberto Carnevalli Airport were suspended for five years while safety procedures and the risks of the mountainous approach were re-evaluated.
Checklist Discipline Reinforcement
The investigation emphasized the absolute necessity of completing AHRS synchronization and following all pre-flight checklists regardless of schedule delays.