OLS.

Contexts in source publication

Context 1

... obstacles. Only some frangible objects (such as visual and-navigational aids required to be there by function) and existing immovable objects (including any other object shielded by that immovable one) can penetrate obstacle surfaces. The obstacle limitation surfaces (OLS) are intended to protect aircraft in flight and consist of the following ( Fig. ...

Context 2

... by combining geometrical data from topographic DTM and functional parameters from airport operational procedures defining the OLS it is possible to obtain a 3D model (Fig. 9). Thus, it became useful managing complex environmental and functional frameworks where orography, anthropic activities, and airport operational procedures interact. Indeed, Fig. 10 gives efficient support to plan (or verify) approach and departure procedures with respect to the natural obstacles in the areas around the airport. For instance, in the area south of the airport, the natural terrain represents an obstacle that penetrates the surface AS33, which is aligned to the runway centreline to allow ILS ...

Context 3

... analysis should not ignore the geometrical detail of singular obstacles penetrating OLS that cannot be observed in the 3D representation. The automatic VBA procedure has identified 589 obstacles to be compiled and analysed. In the case study, 162 obstacles more than those listed in the current Aerodrome Obstacle Chart type A have been identified. Fig. 11 shows the statistical distribution of the assessed collision risk. It shows that the number of obstacles decreases when the risk ...