What happened
During a climb through 3,000 feet mean sea level, approximately 4 nautical miles from the airport, a low pressure turbine module separated from the engine and departed the aircraft. The incident occurred while the aircraft was climbing.
The investigation
An examination of the engine's internal components revealed significant debris and blockages:
- The B-sump forward scavenge screen was completely blocked with coke and contained metallic flakes, the largest measuring 1/3 inch by 1/3 inch. This screen was also partially collapsed.
- The B-sump aft scavenge screen was approximately 90 percent blocked and contained metallic flakes.
- Oil samples from both the B-sump forward and aft scavenge lines were black and contained black particles.
- The C-sump forward scavenge screen was roughly 75 percent blocked with coke, though the center portion remained clear.
- The C-sump aft screen was 5 percent blocked.
- The oil filter contained black oil and black particles, and the bypass button had popped.
Findings
Investigation of the engine components identified extensive contamination and mechanical failure, specifically noting the presence of coke and metallic flakes within the scavenge screens and oil filter.