Page:NTSB Aircraft Accident Report, United Airlines Flight 389.pdf/17

 the four emergency exit windows, portions of the engine cowls of all three engines, portions of the fuselage from the radome to the empennage, and portions of both wings with parts of their attached components including both wing tips. All or part of all major components including control surfaces were recovered.

Following recovery of the Nos. 1 and 2 engines and portions of No. 3, the engines were disassembled and inspected. Both Nos. 1 and 2 were relatively intact but badly damaged although the damage to No. 1 was less severe.

Examination of the No. 1 engine revealed that there were no signs on operational distress or overtemperature operation. The bearings and lubrication system showed no evidence of preimpact failure or inadequate lubrication. The turbine section had evidence of rotational rubbing on both rotating and fixed components. The front compressor drive shaft was intact and had no perceptible twisting. However, there was a measurable runout of the shaft which varied from .003 inch at the No. 4 1/2 bearing location to 1.295 inches forward of the splines. A number of compressor blades on the front and rear compressors were bent opposite the direction of rotation and there was damage on the leading edges of many compressor blades and trailing edges of many stator vanes. Damage to the trailing edge of the stator vanes was in the direction of rotation. There was no evidence of operational distress in the combustion chambers or combustion chamber inner cases. The first stage nozzle guide vanes showed little evidence of foreign object damage but there were light aluminum splatters on the vanes. The fuel manifold was pressure checked and exhibited no evidence of fuel leaks. The clamshell doors were just out of the "open," forward thrust position.