In order to solve the problem of large power difference between forward pushing and backward pulling of a certain type of airborne hydraulic damper, the sealing structure and the exhaust structure of the damping chamber were improved. The failure mechanism was analyzed and it was determined that the abnormal starting force caused by the unreasonable seal setting and the decrease of the damping performance in the extension direction caused by the insufficient internal oil led to the difference of the starting force of the side rod device. The results show that the design can improve the sealing performance of the damper and meet the requirements of the starting force of the system.