Investigation Summary
The flight was a short hop from Quito to Tulcán, a high-altitude airport in the Andes. During the NDB approach to Runway 23, the crew was required to fly over the airport, then perform a teardrop turn to align with the runway. Investigation revealed the crew entered the approach at 230 knots, well above the 180-knot limit for the procedure. Furthermore, the pilot used a shallow bank angle of 15 degrees instead of the standard 25-30 degrees. This combination of high speed and wide turn radius caused the Boeing 727 to drift nearly 20 miles off course, directly into the side of the 15,626-foot Cumbal Volcano. The wreckage was discovered 24 hours later in a crater near the volcano's summit.
Final Conclusions
The Special Administrative Unit of Civil Aeronautics concluded the primary cause was the pilot's decision to continue the approach despite meteorological conditions being below safety minimums. Contributing factors included poor navigation execution, excessive airspeed during the approach procedure, and failure to maintain the prescribed flight path in mountainous terrain.
Video Analysis
No video analysis linked for this case file yet.
Systems & Failure Modes
NDB (Non-Directional Beacon)
A ground-based radio transmitter used for navigation; the crew failed to fly directly over the beacon as required by the approach plate.
GPWS (Ground Proximity Warning System)
The aircraft was equipped with early-generation warning systems, but the high speed and mountainous terrain likely left insufficient time for recovery once the alert sounded.
Interesting Facts
- 01The aircraft was named 'El Oro' and had been in service since 1967.
- 02The Captain was a flight instructor with over 12,000 total flight hours.
- 03The approach was conducted in foggy conditions with low visibility.
- 04The crash site was located approximately 20 miles north of the destination airport.
- 05The impact occurred at 10:23 AM local time.
Safety Actions & Advisories
Decision Making Training
Investigators emphasized the use of the DECIDE model (Detect, Estimate, Choose, Identify, Do, Evaluate) to improve pilot decision-making in deteriorating weather.
Approach Speed Adherence
Reinforcement of strict adherence to published approach speeds and bank angles, especially in high-altitude mountainous environments.