Incident Summary
During the takeoff rotation of an aircraft, the fire bell and the number 2 engine fire warning light activated. The crew also noted a power loss on the number 2 engine. Despite the warnings, the takeoff was continued. The crew secured the affected engine and discharged the fire extinguishing bottles, but the fire continued to burn. After circling, the aircraft executed a normal approach and landing. Due to the overweight landing, the brake system overheated. No other damage or injuries were reported.
Investigation Findings
A teardown examination of the engine revealed the root cause of the incident. A compressor blade on the 6th stage of the high-pressure compressor (HPC) rotor had separated due to fatigue. The failed blade subsequently damaged the 7th and remaining stages of the HPC rotor. This damage ignited a titanium case fire. Metallurgical analysis indicated that the fatigue crack originated in the dovetail area of the blade.
Conclusion
The investigation determined that the engine fire was caused by the fatigue failure of a 6th stage HPC rotor blade, which propagated from the dovetail area. The crew's actions in continuing the takeoff and securing the engine were performed, though the fire persisted. The overweight landing resulted in brake overheating but no additional damage or injuries.