Incident Overview
On an unspecified date, a twin-engine turboprop aircraft (registration YV2653) departed from runway 07 at airport SVRS under visual meteorological conditions (VMC) with 10 persons on board (pilot and 9 passengers). After takeoff, the crew completed the after-takeoff checklist and continued a normal initial climb. Approaching flight level 165, an anomaly occurred with torque indication fluctuation and loss of oil pressure on the left (LH) engine. The captain immediately applied the procedures from the Quick Reference Handbook (QRH) but did not obtain satisfactory results. The crew decided to return to the departure airport and notified Barcelona Approach Control of the situation. They were authorized to return. During final approach, the left engine was secured and shut down in accordance with the manual. In contact with the tower, the crew was cleared to land on runway 02 and requested firefighting assistance as a precaution. The landing was uneventful, and all passengers and crew were uninjured. The aircraft sustained the left engine anomaly.
Aircraft and Crew
The aircraft was a twin-engine land plane powered by two Pratt & Whitney Garrett Canada PT6A-20A turboprop engines, classified under General Aviation – Corporate Use. It held a valid airworthiness certificate issued by the Venezuelan Aeronautical Authority (INAC) and an FAA type certificate (A8EA). The last scheduled maintenance was performed by OMAC No. 643 (Servicios Flyteline, C.A.) at Maracay, Aragua state. The pilot in command, aged 29, held a valid commercial pilot license for helicopters and medical certificate issued by INAC, with instrument rating and BE9L captain type rating. Weather conditions were CAVOK.
Investigation
The investigation included review of aircraft documentation, crew licenses and logs, maintenance records, interviews with the crew, and technical inspections of the left engine. Inspections comprised borescope examination, hot section inspection, chip detector analysis, power section check, and first-stage compressor inspection. The borescope findings showed erosion and cracks within permissible limits, and carbon accumulation. No metallic particles were found in filters or chip detector. The engine run-up indicated normal parameters, with no subsequent oil leaks.
Findings
The investigation determined that there was no evidence of internal mechanical failure in the left engine. The causal analysis indicated that the event did not originate from a technical failure but from the alignment of human and organizational factors.
Probable Cause
The probable cause, as determined by the Accident Investigation Board (JIAAC), is that the event was not caused by a technical failure but by the alignment of human and organizational factors. No specific details of those factors were provided in the report.