The booster motors, each attached to and surrounding a centerbody, are mully connected to each other via one or more hollow manifold legs through which propulsive gases flow freely. At a predetermined time, the manifold cutter receives a signal activating the cutter to sever the manifold leg. Upon severance, the cut manifold leg still attached to the booster acts as a nozzle by venting residual propulsive gases and thereby propelling the booster away from the centerbody.