INVESTIGATION OF SURFACE INTERACTIONS OF THE OLS AND CNS WITH URBAN PLANNING IN TERMS OF AVIATION SAFETY AND SUSTAINABLE DEVELOPMENT OF CITIES

INVESTIGATION OF SURFACE INTERACTIONS OF THE OBSTACLE LIMITATION SURFACES AND NAVIGATION AIDS (CNS) WITH URBAN PLANNING / CITY PLANS IN TERMS OF AVIATION SAFETY AND SUSTAINABLE DEVELOPMENT OF CITIES

While aviation continues to promote states' socio-economic growth and development, it also imposes some constraints on the environment, including urban areas. Due to the growing population, increasing numbers of vertical structuring and its integration with the transportation networks continue to develop and progress in cities. As urbanization increases with the developing technology, the horizontal-vertical structuring speed is advancing at the same rate. On the other hand, developments in aviation industry contribute to the growth and advancement of people's business, trade, tourism, and social interactions on a global scale. It is estimated that more than half of the world's population will live in urban areas by 2050, which will lead to more travel demand and a rise in airport facilities. The International Civil Aviation Organization (ICAO) predicts that worldwide aircraft movements and passenger volumes will double by 2030. In this context, it is critical that public authorities need to take into consideration of some investments to improve their infrastructure and to support this expansion of demand on a global scale to manage this relationship and mobility. In addition, it is essential to meet the social, economic, and environmental needs of the society for a sustainable growth.

Airports and their surroundings are the areas that carry the highest risk for aircraft to continue their operations safely. Hence, these areas require special planning with 3D spatial analysis. Urban movements, especially owing to the increasing demands for vertical construction in the airport surroundings, may cause the violation of the airspace that must be protected for flight operations. High-rise constructions that negatively affect signals increase flight safety risks for aircrafts taking off and landing or re-landing on the runway in an emergency. For this reason, obstacle limitation surfaces (OLS) and navigation aids restricted areas (CNS BRA) have been defined by ICAO to ensure flight safety in aviation operations. These areas also clear the airspace from obstacles around airports, and thus they provide safe air traffic operations for departing and approaching aircraft. These surfaces are partially detailed in ICAO's Annex 14 and Annex 15 documents.

Obstacle Plans consist of surfaces defining the height constraints around the airport and comprise all the constructions in the plan boundary. Moreover, master plans (city development plans) are the plans in which the development direction, usage functions, and mass sizes of urban settlement areas are designed both horizontally and vertically according to future population projections. These plans, in addition to being a reference for all kinds of urban studies according to the development axes of the city, also determine the commercial areas and the limitations of maximum permitted height of building (hMAX) and Floor Area Ratio – Lot Coverage?according to the development axes. Today, inadequate integration of master plans with obstacle plans can cause problems in terms of aviation safety and the sustainable development of cities in many countries.

The discrepancies observed in the synergistic relationship between the building heights in the master plans and the obstacle plans together with CNS BRA areas cause the increasing number of structures violate the restricted airspace for flight operations. While traditional planning approaches take into consideration of two-dimensional planning patterns and not having sufficiently thought the elevation (Z, 3D) information, and similarly, without adequately interpreting the current master plans with respect to OLS regulations, has created the basis of the problem between the aviation and urbanization industries. When there is a confliction between these height restrictions and the construction rights in the master plan, some aggrievements occur in terms of right/property owners. To prevent and/or solve this problem, it is important to keep the compatibility of existing structures around the airport, planned /to be planned development rights, and (OLS) obstacle plans under control by using sustainable GIS technologies.

In our key solution to fix this problem, there are some technical solutions applied with unique methods in different CAD and GIS software to the creation of obstacle limitation surfaces and CNS BRA areas according to ICAO Annex 14 and Annex 15 standards. In terms of inter-institutional interaction and sustainable functionality, the capabilities of www.obstacleanalze.com, our web-based GIS solution, take place as an effective solution at this point. It has a number of useful tools both for the aviation and urban planning authorities in Turkey and all around the world where they may monitor, design and analyze the elevation restrictions in obstacle limitation surfaces.

Dudu EROL, Serdar BAYBURT, ?zgür KARATA?