Page:NTSB Aircraft Accident Report, United Airlines Flight 389.pdf/19

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of rotation and separated from the inner support. Approximately 50 percent of the second stage compressor blades of the front compressor were bent opposite to the direction of rotation. The remainder of the blades were bent aft. The third stage compressor disk was recovered separately with three compressor blades attached. These blades were bent 20-30 degrees in a direction opposite to rotation. The face of the disk was severely rubbed.

The recovered fuel boost pumps, valves, and fuel system components showed no evidence of malfunction or operational distress. There was no evidence of fire or overpressure in the fuel system plumbing except the sooting of two pieces. One was a section of fuel dump tubing and a connector assembly with sections of tubing attached. In the fuel dump tubing, sooting was seen over deformed areas, and in the connector, an area of deformed tubing pulled away from the inside diameter of the connector was not sooted, leaving a clearly defined line corresponding to the area that is normally under the connector. Approximately 75 sections and fragments of other fuel system tubing and tank structure were recovered and exhibited no evidence of fire, explosion, or electrical arcing.

The Nos. 2 and 3 thrust reverser clam shell doors were in the (forward thrust positions), and the Nos. 2 and 3 reverser lockout actuators were in the locked position. The directional control valve rocker arm of the No. 1 engine was bent outboard and broken off. The thrust reverser followup cam was free and the directional control valve could be operated manually.

The thrust reverser control cam was in a position to have either the cam roller or the directional valve control in the reverse position. When the broken sections of the control arm were matched, the control valve was in the reverse thrust position.