Evaluation of Sample Helicopter Tail Rotor Pitch Link Beaarings by DynamicTesting Using Simulated Load/Motion Conditions

摘要

This report describes the testing performed on helicopter rotor pitch linkbearings. The purpose of the testing was to evalua;te a new liner material situated between the ball and race of each bearing. The bearing material would be expected to endure a severe simultaneous cyclic loading and oscillatory motion, as is experienced in bearings of present day helicopters when they are maneuvered. Twenty-two bearings were submitted for test by the Naval Air Development Center (NADC) under Contract N62269-90-C-0247. A total of 9600 hours of bearing testing was scheduled for 12 of the 22 bearings. In the event of premature failures, the other 10 bearings were to be used. Six of the 12 bearings would be subjected to a Type I testing and the other six to a Type II testing program. The difference between the Type I and Type II testing was the level of load applied to the bearings and the angle of motion through which the bearings were oscillated.