Colombia

Failure of the right main gear during taxi due to the presence of corrosion in the trunnion.

The decision of the crew to abandon the takeoff procedure at a speed that was 12 knots above the V1 speed on a wet runway surface, following an EGT warning on engines n°1 and 4. The following contributing factors were identified:
- Failure of the crew to take into consideration the wet runway factor in the takeoff performances calculation,
- Absence of a flight dispatcher properly certified and qualified for the equipment,
- Failure of the engine number n°1 for undetermined reasons.

A possible fuel contamination affected the power on one engine or both. The aircraft was overloaded at takeoff, which, compounded by the considerable loss of power to the engines due to the altitude of the aerodrome, did not allow the pilot to maneuver the aircraft to return to the runway. In addition, the center of gravity, despite being within the permissible limits, was too far behind for an operation in adverse weather conditions.

As the accident occurred in an area with hostile rebels, investigators were not able to reach the scene and to access to the wreckage and debris. Thus, the exact cause of the left engine failure could not be determined with certainty.

The non-observance of the procedures described for an engine failure after V1, especially those relating to the maintenance of safe takeoff speed of 84 knots, the retraction of the flaps, automatic operation of the landing gear lever and the use of contingency power. The erroneous operation of the fuel-flow-control lever (FCL) of engine number one, the move from the open to the closed position during the chain of events, which left the plane and the inappropriate use of the fuel-flow-control lever (FCL) of engine number two, to bring it to the MAX NG position in an attempt to obtain performance of the engine. Maintaining an attitude of the plane on take-off after nr. 2 engine failure with the consequent reduction of speed and then maintaining the aircraft in a climbing attitude, after an engine shutdown, which came at stall speed and the subsequent lack of control of the aircraft. The failure of the engine for undetermined reasons during the takeoff roll, after V1, which forced the crew to perform a series of emergency procedures to deal with the fault and continue with the initial climb. The absence or failure of resource management among flight crew members during the sequence of events. The unmeasurable reduction in the situational awareness of the crew as a result of the financial situation of the company and the divorce in which the Captain of the aircraft was involved.

The accident was caused by a chain of errors and mistakes which began by accepting and carrying out a hasty descent that led to the omission of key points in the checklist such as the arming of the spoilers, excessive descent rate and speed and a configuration that led to faulty placement of the aircraft on the runway in abnormal conditions and 862 meters from the normal touchdown point. These conditions caused a vibration of the right main landing gear that could not be controlled by the Shimmy Damper, allowing higher loads to the strength of the undercarriage, which broke.

Controlled flight into terrain after the crew took the decision to continue the approach under VFR mode in IMC conditions until the aircraft impacted terrain. Poor CRM and lack of situational awareness were considered as contributing factors.