Landing slot

A landing slot, takeoff slot, or airport slot is a right granted by an airport owner which allows the slot holder to schedule a landing or departure during a specific time period.

Landing slots are allocated in accordance with guidelines set down by the IATA's Worldwide Airport Slots Group. All airports worldwide are categorized as either Level 1 (Non-Coordinated Airport), Level 2 (Schedules Facilitated Airport), or Level 3 (Coordinated Airport).

Allocated landing slots may have a commercial value and can be traded between airlines. Continental Airlines paid $209 million for four pairs of landing slots from GB Airways at London Heathrow Airport, $52.3m each. The highest price paid for a pair of take-off and landing slots at Heathrow Airport was $75m, paid by Oman Air to Air France–KLM for a prized early morning arrival, reported in February 2016. A year before, American Airlines paid $60m to Scandinavian Airlines.

As demand exceeds supply, slot trading became the main solution to enter Heathrow and transfers grew from 42 in 2000 to 526 in 2012 and over 10 years the average priced slot increased prices by £4 per passenger.

If an airline doesn't use an allocation of slots (typically 80% usage over six months) then it can lose the rights. Airlines may operate ghost or empty flights to preserve slot allocations.

No Level 3 designation, but nevertheless slot controlled:

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