All decisions made by controllers can have critical safety consequences. Extraordinary situations may arise due to different weather conditions such as snow in the air/ground or thunderstorms, heavy rain, etc. Additionally, situations in which traffic management is intense can become burdensome for the controller. Planning becomes more and more complicated and no optimal decision can make the situation even more complex. One way to overcome this problem is to use electronic support systems. Assistance systems exist for several types of controller tasks, such as aircraft approach ("Arrival Manager", AMAN), departure ("Departure Manager", DMAN), or ground navigation. In case of Arrival phase: AMAN – suggests the order in which the aircraft lands and provides the required commands. This helps give optimal planning from a system perspective.