What happened
On December 19, 2023, a Piper 32R-300T, registration HK4773G, departed Barrancominas, Guainía, for a return flight to Villavicencio. The aircraft was carrying one pilot and two passengers, including a minor, along with a cargo of fish.
Shortly after takeoff, while climbing through approximately 400 feet, the pilot noticed a burning smell and white smoke emerging from the right side of the cockpit pedestal. The pilot attempted to turn back toward the departure airfield, but the smoke intensified, significantly reducing visibility and making breathing difficult. After assessing the critical situation and observing signs of fire, the pilot determined that a landing at the airfield was not possible due to low altitude, nearby trees, and the risk to populated areas.
The pilot executed an emergency water landing on the Guavia le River. Although the pilot maintained control during the impact, the aircraft overturned upon hitting the water and sank rapidly. The two adult occupants managed to evacuate the sinking aircraft and swim to the shore. However, the minor passenger was separated from the group during the swim. Following an intensive search by local authorities, the minor's body was recovered two days later, approximately 500 meters from the accident site.
The investigation
The Colombian investigation authority (DIACC) examined the wreckage and the engine compartment. The investigation focused on the failure of the turbocharger system and the maintenance history of the aircraft. Investigators analyzed the engine's exhaust system, specifically looking for evidence of the failure of the exhaust gas outlet tube. The investigation also reviewed maintenance practices regarding the use of approved parts and compliance with existing Airworthiness Directives (AD).
Findings
- The primary cause of the emergency was the failure of the turbocharger system, specifically the detachment of the exhaust gas outlet tube.
- The failure of the clamp (P/N MVT65861-377) allowed hot exhaust gases to escape, directing them toward the firewall. This resulted in smoke and fire entering the cockpit.
- Maintenance errors were identified, as the operator failed to comply with the manufacturer's requirements outlined in AD 91-21-01-R1. Specifically, the operator used a non-aviation grade element as a safety wire for the turbocharger clamp and failed to maintain the required dimensions for the assembly.
- A contributing factor was the lack of proper flight planning regarding the transport of a minor, as the operator and pilot had not clearly established the necessary supervision or responsibilities for the passenger at the destination.