Theorie Basiskurs

We already know some information from the introduction to the topic of airspace. Nobody flies around the sky without permission. The second important rule is that no one is going anywhere on the airfield without permission, neither by car nor by plane.

Imagine two airplanes approaching each other on the runway, or a vehicle driving across the runway while you want to land, or two jumbo jets parking simultaneously and colliding with the wings. Total chaos would be the result if each pilot could decide for himself when to go where, or fly in controlled airspace.

To coordinate this there are air traffic controllers in the tower who have everything in view and decide the order. The air traffic controllers in the tower are primarily responsible for coordinating everything that takes off or flies, while at larger airports Ground Control are responsible for everything that taxis and parks. 

NOTE:

A pilot always sends a request before he wants to start his engine, as soon as he gets that permission he can start.

If the aircraft is ready for taxiing, the request for taxi clearance to the active runway is always made, before the aircraft is allowed to move. This clearance must be obtained for and part of this taxi clearance is the assigned route, e.g. from A via B and C to D. This must be explicitly followed, otherwise there could be oncoming traffic, or you get lost and end up at the wrong end of the runway. It is already known from the chapter on radio and communication that such information has to be repeated back to ensure that it has been understood correctly. The rule is: Request-Clearence-Repeat for confirmation. Furthermore It is expected that whoever requests is willing to carry out the clearance without delay.