Abstract: To solve the difficulties in aircraft multidisciplinary design optimization,the ring-shaped graphical network of design layout,the determination method of main design variables,the thrice golden section method for the level decision of orthogonal design and the non-dimensional multi-object method are presented in the new algorithm,and combining the orthogonal iteration and neural network,the new algorithm is formed to find the optimal solution. The calculation example shows that the new algorithm works effectively in aircraft design.

Key words: aircraft design, multidisciplinary design optimization(MDO), orthogonal design, neural network, golden section method