The one invalidation was caused by oil leakage which lead to surface bonding between the balance gear rim and the small herringbone gear,and the other one was more serious that the track trough in the balance gear surface had been abraded badly and some bate pits occured in the surface and there was a 5 mm fatigue layer.
其中第一次失效是因失油造成平衡大齿轮与小人字齿轮表面产生严重胶合;第二次失效更为严重,平衡轮中间轨道槽严重磨损,轨道面产生脱斑且整个表面已形成5mm深的疲劳层。
