In practical applied aerodynamics, solutions of unsteady time-accurate three-dimensional flows involving multiple bodies in relative motion are frequently required. Typical examples include the store/airframe separation from aircraft or the rotor-fuselage interaction problem in helicopter aerodynamics. Several research works have been previously conducted for the simulation of the complicated unsteady flows involving mutual aerodynamic interference of multiple bodies by solving the Euler or Navier-Stokes equations using either structured or unstructured overset grid methods [1, 2, 3].