Research About Model Of Terminal Area Short Term Airspace Utilization Rate

It is necessary to evaluate the use of airspace accurately by using the reasonable evaluation method.The evaluation of airspace utilization is an effective method to reduce flight delays and ensure the smooth flow of air transportation network.A unified method cannot be used to assess the entire airspace by reason of the diversity of airspace types and different characteristics in airspace systems.While the terminal area is the most complex and busiest airspace,which is the bottleneck in the air transportation network,the evaluation of the terminal area utilization is a key step in the evaluation of airspace utilization.The evaluation of the airspace utilization rate in the terminal area can be used to make full use of the value of airspace resources,and provide a decision-making basis for alleviating the airspace tension in the terminal areas.The study was conducted to evaluate short-term utilization rates of airspace in terminal areas.The main research results are as follows:1.The definition of terminal,the connotation of airspace utilization and the rationality of using "short term" for assessing utilization are clarified;The influence factors and indicators of the airspace from the aspects of time,space,capacity and flow distribution are analyzed.The process method is used,and the operation process of the terminal area is divided into three sub processes: the approach,the departure,and the over flight.The principal component analysis method is used to determine the degree of importance of each sub-process to the operation of the terminal area.The traffic flow conditions is classified according to different control intensity,and the relationship between the airspace utilization model and various traffic flow conditions is carefully analyzed.2.The aircraft fly along the standard procedure when traffic flow is free flow state.From the perspective of capacity and flow respectively,and the minimum safe time interval between aircraft on crossed and non-crossed routes is calculated separately.Based on the flow rate ratio to establish the approach,departure field,and the over flight utilization model;And then a weighted comprehensive evaluation of each sub process model,the evaluation model of terminal area short-term airspace utilization is established.3.Traffic flow is blocking flow state,from the time and space,terminal area route data,traffic statistics,model proportion and the average flight time of the aircraft are considered.The available effective space-time resources and the actual occupation of space-time resources are calculated to establish the model.The last short-term utilization model is obtained by taking into account the degree of weight and the time-varying4.Traffic flow is from free to blocking transitional state,from the time,space,capacity and spatial and temporal distribution of traffic flow.Based on the limited capacity and flow,when the dynamic distribution of traffic is considered,a model is established;By considering the loss of space-time resources at the intersection,an improved airspace short-term utilization model is established.The model is applied to the departure and approach routes and the overflight,and the short-term utilization of the airspace in the terminal area is weighted.