Numerical study of the helicopter release problem considering rotor wake

This paper investigates the impact of the helicopter rotor wake on stores that could be launched from it. With use of unsteady flow solver and 6 degree of freedom equations, different cases of store release will be simulated. The model of helicopter used in this study is a simplified model of the UH-60A Black Hawk helicopter and the store is a simplified version of the Hellfire missile. Experimental validation of the solver and equations used will be conducted before investigating the release problem. Subsequent aerodynamic investigations were then conducted to quantify and analyze the path modification resulting from these perturbations: in hovering flight for different store launching thrust and in forward flight for different flight speeds. Results indicate a notable aerodynamic effect in the stores trajectory for hovering flight, changing its path prevision and altering its precision. For forward flight cases, simulations show lessen impact over the same missile paths.