Abstract: Taking a new type of launch vehicle as the research object，the problem of reconfiguration control under servo mechanism fault was studied.The problem was transformed into a constrained quadratic programming problem，and then a control allocation method combining the Armijo criterion and BFGS algorithm was used to solve the problem.Armijo criterion can ensure the convergence of the optimization algorithm，while BFGS algorithm avoided the inversion of Hesse matrix in the iterative process，and had the advantage of fast convergence.The proposed reconstruction method was compared with the fixed point iterative algorithm.After 8 iterations，the objective function value and error value converged to about ${\mathrm{10}}^{\mathrm{2}}$ magnitude and ${\mathrm{10}}^{-\mathrm{5}}$ magnitude，respectively.However，the fixed point iterative algorithm was not completely converged after 30 iterations，and the objective function value and error converged to about ${\mathrm{10}}^{\mathrm{3}}$ magnitude and ${\mathrm{10}}^{-\mathrm{2}}$ magnitude，respectively.The results showed that the reconstruction method converged faster and had higher convergence precision than the fixed point iterative algorithm.Taking a single engine stuck fault as an example，the simulation results showed that the control effect was the same as that in the case of no fault，which verified the validity and correctness of the proposed method.