Research On Flight Safety Assessment System Based On High-precision Digital Terrain Model

With the advancement of urbanization,more and more high buildings will be built in the area around aerodrome.Most of these proposed buildings are not located within obstacle limitation surface of Annex 14,but they are located in the protected area of airlines.Therefore,they need to be assessed in accordance with the obstacle restrictions of the flight procedures,and we should make sure the influence of the proposed building in flight safety.However,at present,most of the domestic airports still use the manual assessment model for the assessment of flight safety.Not only the evaluation efficiency is low,but also the two-dimensional plane is limited by the assessment method.It is too abstract and cannot demonstrate the threedimensional characteristics of the obstacle confinement surface.Taking Wenzhou Aerodrome as an example,the study analyzes the procedures and modes for manual assessment,and complies civil airfield protection and flight safety with the Civil Aviation Regulations and Industry Management Regulations,and follows the design philosophy of software engineering.A flight safety assessment system consisting of a digital terrain model,a three-dimensional safety-restricting surface and an obstacle assessment module.Firstly,the topographic map is vectorized to obtain the terrain data,and the Delaunay triangulation is constructed to get the terrestrial digital model.Secondly,Gaussian-Kruger projection coordinates are selected.On the terrain digital model,the two-dimensional layer of the constraining surface is drawn first,and then the three-dimensional key nodes are created.The flight safety obstacles are created by using point-based facets.A three-dimensional model of the object confinement surface.Finally,the combination of ArcGIS Engine and DevExpress on the Visual Studio 2010 platform enabled the development of the flight safety assessment system.Systematic tests were conducted through evaluation examples of obstacles and simulated obstacles to prove the reliability of the system.