Design and numerical study of foldable wing module of air-launched underwater glider

Launching underwater gliders by aircraft could greatly expand the application of underwater gliders. However, during the process of the glider entry into the water, it will be subjected to significant impact loads, especially during the process of wing entry into the water. In this paper, a foldable wing module is proposed to reduce the water entry impact loads of the glider caused by the wings entering into the water. The effect of the foldable wing module on impact loads reduction and the influence of the foldable wing module on the water entry trajectory are studied by numerical method. The results show that the differences in mass and gravity center position caused by the foldable wing module have little effect on the water entry impact loads of the glider until the wings impact the water. When the glider enters the water obliquely, the wing module reduces the peak radial acceleration of the glider. In addition, the trajectory and time of the glider to reach the horizontal attitude are also reduced. These conclusions will be helpful for the designing of the wings of air-launched underwater gliders.