Aiming at the task scene of close formation of fixed wing UAVs crossing through the gates, a systematic formation crossing scheme is proposed. Firstly, according to the measurement information of airborne camera, aguidance strategy based on line of sight angle is proposed, which can quickly adjust the nose to aim at the gates; Secondly, in order to improve the reliability of successful crossing and solve the problem of line of sight occlusion, a cooperative guidance strategy based on gate position solution is proposed; Then, in view of the navigation interference in the semi-finals, an inertial navigation system(INS) based on feature point measurement is designed in the horizontal direction. In the vertical direction, the extraction method of air pressure height and vertical velocity based on differential filtering is adopted, and the line of sight angle is used to pass through the gates; A formation control law based on distance control is designed. Finally, the fixed-wing UAV system is designed, and we participated the 2021 Fast Crossding Race of UAV Challenge Competition in a formation of 7 UAVs. The competiton results verify the effectiveness of the proposed method.