Investigation Summary
The accident flight was the final leg of a multi-stop journey that began in Taraira. After diverting to Miraflores due to weather and refueling at San José del Guaviare, the aircraft departed for Villavicencio at 09:55, planning to cruise at 8,500 feet. Approximately 20 minutes into the flight, while climbing through 8,100 feet and roughly 30nm from San José del Guaviare (59nm from Villavicencio), the crew reported problems with the left (number 1) engine. A critical failure in the lubrication system resulted in a massive oil leak, which subsequently prevented the propeller feathering mechanism from functioning. In a twin-engine aircraft like the DC-3, the inability to feather a failed engine is catastrophic as the windmilling blades create massive aerodynamic drag. The crew attempted to divert to La Rinconada aerodrome, but the drag caused a continuous loss of altitude and airspeed. The aircraft crashed only 800 meters from the threshold of runway 05/23 at La Rinconada. Investigators found that the operator's maintenance program was deficient, with no record of a required 50-hour service for the left engine and evidence of substandard repairs on the propeller feathering oil pressure line.
Final Conclusions
The investigation by Aerocivil (Report COL-19-10-GIA) concluded that the primary cause was a loss of control in flight due to the drag generated by the unfeathered propeller following an engine failure. Contributing factors included a malfunction in the number 1 engine lubrication system, deficiencies in maintenance practices regarding the propeller feathering pressure line, and a lack of effective safety management by the operator, which failed to detect errors in maintenance and operational control.
Video Analysis
No video analysis linked for this case file yet.
Airframe & Maintenance
Crew Experience
Captain
Experienced pilot with significant time on the DC-3.
Copilot
Systems & Failure Modes
Propeller Feathering System
A system designed to turn propeller blades parallel to the airflow in the event of an engine failure to stop the propeller from spinning (windmilling) and reduce drag. In this accident, a leak in the oil pressure line prevented this system from functioning.
Pratt & Whitney R-1830-92 Engine
The radial engines powering the DC-3. The number 1 engine suffered a lubrication system failure that led to the emergency.
Interesting Facts
- 01The aircraft was a 74-year-old Douglas DC-3 built in 1945 (MSN 16357 / 33105).
- 02The airframe originally served as a US Navy R4D-7 (Bureau Number 99826) and a USAAF TC-47B-DK.
- 03The left engine (number 1) suffered a total lubrication failure, preventing the propeller from being feathered.
- 04The aircraft was operating a non-scheduled charter flight.
- 05All 14 people on board, including 3 crew members and 11 passengers, perished in the crash.
- 06The landing gear and flaps were found in the retracted position at the crash site.
- 07The aircraft crashed just 800 meters from the threshold of the emergency landing strip at La Rinconada.
Safety Actions & Advisories
Maintenance Program Oversight
The investigation highlighted the need for operators to strictly comply with 50-hour service intervals and maintain accurate flight logs to ensure engine airworthiness.