This paper proposes a cooperative planning framework for multiple low-level penetration unmanned aerial
vehicles(UAVs) by analyzing threat environments interfering factors of cooperative penetration. Based on space confliction,
a strike order coordinate algorithm is designed to preprocess deconfliction. Then a synchronized target assignment algorithm
of varying timing steps is provided to maximize penetration efficiency. An iterative UAV route optimal selection algorithm
is described. Simulation analysis shows the effectiveness of the proposed planning algorithm.