Abstract: On the basis of experimental study of crack combustion of both composite and double base grains a comprehensive static igniting model has been established,which considers heat convection,heat conduction,heat radiation,erosive burning effect and the influence of acoustic oscillation chamber.Two sets of partial differential governing equations have been derived.As a result of their numerical solution variations of many principal parameters have been obtained such as the flame spreading velocity,the pressure distribution,the temperature distribution and the hot gas velocity distribution.The essential behaviours of propellant crack combustion could be easly predicted.For example,the flame predicted spreading velocity is proved in quite good agreement with the experimental data.This model is possessed of extensive applicability not only for the double base propellant but also for the composite propellant.