Originally Posted by kraggy
i thought that airlines paid large amounts of money for these slots and that they would thus be automatic for a certain time each day/week? if so, then why would a pilot ask Twr if they have a slot or not?
Could anyone shed some light on how the slot-time system works from the point of view of the air traffic controller?
I'll try but someone be prepared to correct me.
Slots are not automatic for a certain time of day/week they are issued by the central flow management unit in Brussels every day and are designed to keep the numbers of aircraft flying through any particular sector of airspace to a manageable level. Whilst they benefit the area controllers more they have more of an impact on airfield ops due to the flight having to take-off within a specified time period (-5 mins to +10 mins) of the slot time. If the aircraft misses its slot time then a new slot has to be issued which is when delays start occuring.