Incident Overview
During the initial climb phase of flight, the flight crew heard a loud bang accompanied by airframe vibrations. The control tower notified the crew that smoke and flame were emitting from the left engine. The crew declared an emergency and received clearance to land. The pilot discharged a bank of fire extinguishing agent and shut down the engine. The aircraft landed without further incident.
Investigation Findings
Post-flight investigation revealed that a turbine blade had failed in fatigue. The flight crew had received an indication that the fire extinguishing agent had discharged, but later it was determined that the agent did not discharge due to the installation of an incorrect discharge outlet. Additionally, the rear emergency slide on the right side was slow in inflating and was not usable for the evacuation. When the slide was installed on a test stand, it was found to operate within normal operating parameters.
Technical Details
The turbine blade failure was attributed to fatigue. The incorrect discharge outlet prevented the fire extinguishing agent from being released despite the crew receiving a discharge indication. The emergency slide's slow inflation could not be replicated in testing, suggesting that the issue may have been situational or installation-related.