Abstract: The approach aircraft landing scheduling problem in the terminal area is discussed in this paper. Taking the flights' minimum total delay as the objective function, this paper proposes an implicit enumeration sorting algorithm with packet-based max position shift (MPS) = 1. It takes into account a variety of air traffic control constraints. Firstly the flights in same route bound to group lock, and then the position-matrix is initialized according to constraints, finally the solution space tree is built to search the optimal solution. The computing speed of the algorithm is improved effectively by selecting the boundary conditions, judging the invalid branch, and eliminating second-best series out. The results indicate that the algorithm can apply to complicated air traffic control (ATC) environment, and can greatly reduce the delay and increase airspaces' availability.