Terminal Airspace Design at the International Airport of n'Djili

On arrival, specific trajectories are flown by the aircraft. They are published as charts contained in the aerodrome part of the aeronautical information publication to show how pilots should proceed to start their descent and how to maneuver safely inside the terminal area control and avoid collision with obstacles on ground. Those trajectories are called "Instrument Flight Procedure". For departures from an airport, the pilot follows flight procedures that are called Standards Instrument Departure; whereas for landing at an airport, aircraft are flying trajectories called Standard Terminal Arrival Procedures.The point merge procedure is a way of flying in the vicinity of an airport with the intention of landing after receiving the clearance of the air traffic control unit. It consists of aligning aircraft on curved trajectories in form of an arch whose point are equidistant from a fix used as a merging point which leads straight to threshold of the runway. While flying on the arch, the flight is a bit delayed until it is given the clearance to proceed with the landing maneuver.