Flight Rerouting Path Planning In Severe Weather

The severe weather affects flight security extraordinarily and is the leading cause of flight delays. When the severe weather occurs in flight airspace, the passive ground holding is the unique strategy of air traffic flow management (ATFM) that can be applied in China. The result is that many flights have to be delayed at the departure aiports, the smooth operation of the whole aviation network will be seriously affected, airlines and passengers have to bear great economic losses. However, the rerouting strategy is an effective method for solving above problems, namely temporarily select a new flight path to avoiding the severe weather area. In this dissertation, the establishment of the affected area caused by the severe weather and the flight rerouting path planning in air route flight stage are studied deeply.Various factors affecting the flight security and leading to reroute are comprehensively analyzed. The severe weather occurs in air routes is mainly studied. The method for establishing the static flight forbidden area based on Graham algorithm is proposed. Then, considering the movement and change of the severe weather and stochastic factors, the dynamic flight forbidden area are established. On this basis, the accuracy evaluation method of the flight forbidden area (FFA) is given, and the simulation is made to validate above methods.According to the shape, influence scope, scale and distribution feature of FFA, FFAs are divided into three categories, namely Block FFA (BFFA), Zonal Distribution FFA (ZDFFA) and Scattered Points Distribution FFA (SPDFFA). Aiming at the flight rerouting path planning of BFFA, the flight rerouting model of BFFA is established. Two methods for determining primary rerouting points are given, which are the mehod based on the geometry algorithm and a fast method. Then, the rerouting points are amended under constraints of the heading change, the segment distance and the number of rerouting points, respectively. Finally, the rerouting problem caused by thunderstorms occurring in Southwest China is studied.Aiming at the flight rerouting path planning of ZDFFA, the flight rerouting model of ZDFFA is established. The method for determining the candidate rerouting points around the schedule way points is proposed. Selecting the distance and the average deflection of flight rerouting path as two objectives, the multi-objective dynamic planning algorithm is applied to search the best rerouting path in the network composed of candidate rerouting points and schedule way points. Finally, the flight rerouting paths of Kunming-Haikou in three typical ZDFFAs are simulated and analyzed. Aiming at the flight rerouting path planning of SPDFFA, the flight rerouting model of SPDFFA is established. The method to describe SPDFFA is given in the grid-based environment model. The Non-dominated Sorting Genetic Algorithmâ…¡is applied in the flight rerouting problem, selecting the distance, number of turns and average deflection of flight rerouting segment as objectives. Besides, a new coding method and the deletion operator are presented. Finally, the flight rerouting paths of Kunming-Guangzhou in SPDFFA are simulated and analyzed.In consideration of the flight security, flight economy, air traffic controller's and polit's workload, difference between the rerouting path and the schedule path, flight comfort, 5 indexes are selected to evaluate the flight rerouting path, including the newly added distance, the average lateral deflection distance, the newly added number of turns, the newly added number of large-angle turns, the newly added number of segments crossing adjacent control areas. Then, the pilot-air traffic controller evaluation model, the airlines evaluation model and the comprehensive evaluation model are established by using the analytic hierarchy process, and the index weights of each evaluation model are computed. The flight rerouting paths obtained in each simulation example are evaluated by using above three evaluation models, respectively.In addition, the air traffic flow model with consideration of the rerouting strategy is primarily studied. The dynamic multi-airport air trffic flow model is proposed, and the objective function and constraints are given. In the objective function, the cost of flight delays is deeply analyzed. Current civil aircrafts are classified by using ISODATA algorithm, and the delay cost for each class is given.The core of the dissertation is a deep research on the problem of flight rerouting path planning in the sever weather. The proposed methods have strong pertinence and are easy to be realized. The research of this paper is conducive to improve our country's study level in this field, and provide the theory preparation for the further application of the flight rerouting strategy.