Aiming at involute spline pairs in aerial drive systems,with dissipated energy method,calculation formula for fretting wear amount was established.Besides,for three working conditions,the effects of working conditions on the distribution characteristics were studied.Consequently the conclusions were obtained as follows.Under ideal working conditions,the wear of each tooth is nearly the same,and root contact end on external spline tooth profile acts as the maximum wear position.When there is a lateral gap,th...