As aerospace systems progress toward increased performance, new challenges exist in the store clearance process. Successful prediction of the store separation trajectory involves not only the dynamic and aerodynamic properties of the store, but also the interaction of the store aerodynamics with the aerodynamic flow field of the vehicle. Numerous test and analytical methods exist for computing store trajectories, however new operational requirements continue to create demand for reliable prediction of a broad range of configurations. This demand for advance predictive methods is critical, as the risk of collision of stores with aircraft must be mitigated before any performance enhancement can be incorporated. This paper describes a system for simulating store separation trajectories using databases of steady and unsteady aerodynamic information. The unsteady and steady aerodynamic content is combined to create ensembles of trajectory realizations each representing different release time with respect to the unsteady flow field. Probability distributions of significant events are then calculated. This method has been developed into a software system referred to as the Rapid Unsteady Store Analysis Tool (RUSAT).