Page:NTSB Aircraft Accident Report, United Airlines Flight 389.pdf/18

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The No. 2 engine was recovered with the fan section and the first two compressor stages separated from the rest of the engine. The front accessory drive was not recovered. The recovered compressor blades of these stages were bent opposite the direction of rotation and the stators were bent and damaged in the direction of rotation. The majority of the compressor blades in the remainder of the front compressor, through the sixth stage, were bent opposite to rotation and the stators bent in the direction of rotation. There was no evidence of inadequate lubrication found in the engine. There was damage to the seventh through the twelfth stage stators on the trailing edges, in the direction of rotation. There was foreign object damage to the leading and trailing edges of the thirteenth stage stators. The compressor blades of the rear compressor were bent opposite rotation and showed some tip rub damage. There was no evidence of heat distortion or uncontrolled burning in the combustion chamber assemblies. There was no evidence of overtemperature in the nozzle guide vanes. The front compressor turbine drive shaft was separated at a point 53.5 inches from the forward face of the second stage turbine disk mounting flange. The break spiralled at an approximate 45-degree angle to the longitudinal axis of the shaft. The shaft was bent forward of the No. 4 1/2 bearing. The first three turbine stages showed minor rotational damage. There was no evidence of operational distress in the turbine section.

The fan inlet case assembly of the No. 3 engine inlet guide vanes remaining in the case were bent in the direction of rotation and six of them were broken on the hub end The front compressor front hub and blade assembly was recovered with most of the blades attached. The blades were twisted and bent opposite the direction of rotation There was no evidence of operational distress on the hub. The recovered stator vanes of the first stage were bent opposite the direction