Trajectory and attitude deviations for internal store separation due to unsteady and quasi-steady test method

The deviations of trajectory and attitude angle for internal store separation are evaluated by two wind tunnel test methods. One is the Freedrop Test (FDT), which is known as unsteady and time-dependent method of scaled model. The other is the Captive Trajectory System (CTS) test, which is usually regarded as a quasi-steady and time-averaged test technology. The result shows that there is a streamwise adverse pressure gradient on the cavity resulting in a nose-up pitching moment coefficient (>0) acting on the store model. When the initial pitch angular velocity is 0, the store exits the shear-layer with a nose-up pitch attitude causing the store to climb back towards and collide with the aircraft. However, the store passes through the shear-layer into the freestream with a nose-down pitch, which causes a successful separation event when the initial pitch angular velocity