Experimental study on ballistic stability of truncated cone projectile in high-speed oblique water entry

In this paper, the high-speed photography technique was used to study the high-speed oblique water entry of truncated cone projectiles, and the effects of nose shape, projectile velocity and entry angle on the cavity and ballistic characteristics of oblique water entry were discussed. The experimental results show that the influence of nose shape on the oblique water entry cavity and ballistic characteristics is related to the nose wetted area. For the same type of projectile, with the increase of projectile velocity, the cavity size becomes larger at the same penetration displacement and the surface closure time gets longer. Moreover, with the increase of entry angle, the surface closure time decreases, the velocity attenuation gets faster, at the same penetration displacement the cavity opening length becomes shorter and the cavity asymmetry weakens. Additionally, the results indicate that the trajectory stability of the truncated cone projectile varies under different water entry velocities and attitude angles.