摘要
The purpose of Federal Aviation Regulations Part 77, entitled ＂Objects Affecting Navigable Airspace＂, is to identify potential hazards and prevent adverse impacts to the safe and efficient use of navigable airspace. The OIS （obstruction identification surfaces） represent these regulations, identify objects that penetrate these imaginary surfaces, evaluate hazardous effects, and ensure safe separations of aircraft from obstructions. The OIS evaluation is often used for selecting airfield locations and runway orientations. More importantly, the OIS evaluation is an airport＇s safeguard against flawed urban development, especially for airports near rapidly expanding cities. Without accurate analysis tools, hand-calculation errors on the OIS can occur and cause adverse impacts to airport safety. Applying the GIS （geographic information system） features of geospatial data and 3D formats, this paper proposes a model named GIS Obstruction Model which is capable of precisely calculating maximum allowable heights and creating visual imagery of penetrating obstructions. The special features of the model include web-based design, adaptability to any airport, user-friendly multiple inquiry methods, quick response to online inquiries, and response with 3D visual reality. The proposed G1S Obstruction Model is useful for airport planning, architecture design, safety management or civil engineering permit review.
