Mitigating impact loads during water entry by utilizing the air-spring effect

In this work, a load reduction method with a simple structure is proposed to address the threat of the huge slamming loads caused by high-speed water entry. By opening holes in the water-entry attack area and using the compressibility of the air cushion formed in the closed cavity, the air cushion and water in the hole are coupled as a buffer medium to reduce the load during the vehicle water entry. The arbitrary Lagrangian–Eulerian (ALE) algorithm is used for numerical verification. The load characteristics of the vehicle are studied for different opening modes under two typical water entry angles. The pressure distribution of the medium in the hole under different opening modes is analyzed. The load reduction effect and influence of the air spring are also explored, and the specific load reduction mechanism of the air spring is discussed. Finally, considering the application prospects of the load reduction method proposed in this paper for complex structures, a numerical model of the water landing process of a large passenger aircraft with an air spring load reduction configuration is established, and the overall load characteristics during the landing process are studied.