Abstract
Obstacle defines all fixed and mobile objects, or parts thereof, that are located on an area intended for the surface movement of aircraft or extend above a defined surface intended to protect aircraft in flight or stand outside those defined surfaces and that have been assessed as being a hazard to air navigation. Aircraft operations are based on electronic supporting systems using radio frequencies to assist pilots. These frequencies can receive outside interference that change their courses or power, such as distortion, attenuation or reinforcements by an obstacle. This is a preliminary case study that shows the relation of instrument flight procedures and the degree of interferences introduced by a planned obstacle, which is a main bridge post, within the service volume of the radio navigation aids. For the purpose of this study, the case airport's data and it's VOR/DME and ILS systems' limitations are analyzed, as well as the relation of interferences between the obstacle and navigation aides were reviewed with the internal regulations in Korea.