Abstract: There’s always a 3-D acceleration limit during transporting, loading, and discharging precise Heavy lift cargos. To avoid the acceleration generated from collisions between hatch and swaying cargos exceeding the limit, it is necessary to use endergonic soft cushions to control the acceleration in a reasonable scope. What this paper analyzes is, based on the maximum kinetic energy organized from cargo movement, considering the bearing capacity of the impulsion surfaces, how to reduce accelerations by using air bag buffer. This paper builds the air bags calculation model employing the law of conservation of energy, and then obtained the curves fitting the air bags forces-location data, thereby the impulsion acceleration can be calculated. The model is further verified by experiments. It is shown that, when using the same air bags to buffer cargos with different weight, the impact acceleration can be controlled effectively by changing the initial pressure.