The article describes the main provisions of a mathematical model of the survivability of a complex object in a drawing massive air strike, reflecting the process of leaving drums of aviation complexes of the enemy in a given area and to overcome them multifunctional air defense system under cover of objects by means of an integrated (electronic and fire), and taking into account the two-way nature of the conduct EW. The model is based on the representation of these processes in the form of semi-Markov processes described by direct integral-differential equations of the principle of state space extension and application of the Laplace transform.