Investigation of Hydrodynamic Ram Behavior Using Newly Established HRam Gun System

The hydrodynamic ram (HRam) phenomenon is one of the primary factors to cause catastrophic structural damage of aircraft. It is important to investigate HRam behavior on aircraft for estimating structural survivability which is one of the main issues for aerospace survivability and defense department of governments. In this paper, HRam gun system which we developed was introduced and HRam test was conducted on welded metallic T-Joint. The dynamic failure behavior and ability to withstand HRam pressure were investigated using strain gages and pressure sensors with high-speed cameras. The test results show that the test system can generate HRam pressure waves and get the dynamic failure characteristics of the T-Joint. It is expected to economically simulate HRam phenomenon for the purpose of investigating failure characteristics on aircraft skin–spar structure.