Air traffic control has multiple sectors. Nowadays the number of smaller flying objects, such as drones or smaller planes is increasing, which makes air traffic control from traditional Airport traffic control towers harder. Due to this, „free flight” is becoming a more and more actual problem. One of the main problems that require a solution during free flight implementation is collision avoidance, which is also a safety critical feature. During my thesis I have analyzed multiple control methods which are all capable of allowing planes to avoid collisions without the use of an Airport traffic control tower, then allow these planes to return to their original path, and continue the flight. This paper contains the theory, implementation and simulation results of the different collision avoidance algorythms and also a comparison of their efficiency. I have analysed three different methods, which are the following: the first one is a protocoll-based method in which I have simulated two types of conflicts, exact and non-exact. After this I have implemented and simulated a fuzzy based control. The last method which I have implemented and simulated is based on multi-agent game theory.