Intro to Airway Slots in Europe, Eurocontrol, and the NM

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Intro to Airway Slots in Europe, Eurocontrol, and the NM

Intro to Airway Slots in Europe, Eurocontrol, and the NM

For business aircraft operators, managing airport slots and airway slots within Europe is something of an art and a science. There are steps you can take to avoid slot delays, and there are effective responses to minimize delays when they occur. Sometimes, though, it comes down to experience and instinct in knowing how to avoid major slot delay situations. Your 3rd-party provider will assist on both fronts and ensure best opportunity for a no-delay operating experience to, from, and within Europe.

If you are new to Europe’s slot system, here is some general info to help you understand it:

1. Airway slots are used to manage en-route capacity in Europe

Eurocontrol uses airway slots to match supply and demand and to control airway capacity on a daily basis within Europe. Airway slots are given if demand outstrips supply, and anyone who files an IFR flight plan in Europe could be subject to an airway slot. Airway slots are provided to operators up to two hours before departure and specify a time for the aircraft to enter a particular airspace. These airway slots apply to operations within the European Union (EU) or when departing from the EU to a destination outside of Europe.

2. It is the NOC that issues slots

The Network Manager (NM), or Network Management Operations Centre (NMOC) (previously the Central flow management unit [CFMU]) is the operational unit of Eurocontrol and is responsible for airspace management in Europe from the north edge of Africa, including Morocco, west to Ireland, north to Finland, and east to Turkey. Air traffic flow capacity management (ATFCM) is the service the NM provides to operators, and enhanced tactical flow management system ( ETFMS) is the tool used to collect data from air traffic control (ATC) systems around Europe to build a 24/7 ‘picture’ of current traffic levels.

The change of name follows the nomination by the European Commission in 2011 of Eurocontrol as the single entity responsible for network management in Europe under the long term ‘Single European Sky’ initiative.

3. Airway slots occur depending on congestion

An aircraft will only be subject to a slot delay if demand outstrips supply and if other capacity management tools available to air traffic have not sufficiently mitigated the issue. If an airway slot is required, it will be issued no more than two hours before flight. You’ll either receive: 1) an “unrestricted flight” message, which is a flight without a slot delay, or 2) an on-time slot with a -5 /+10 minute deviation based on the time you leave the aircraft parking stand that matches your estimated off block time (EOBT), or 3) a slot delay also known as an airway slot with a similar -5/+10 deviation. If you miss your slot time and re-file, you may be placed at the back of the queue and experience additional delays.

4. There is no fixed number of airway slots per hour

Unlike airport slots which are normally capped at the physical capacity of the runway and airport infrastructure, there is no minimum or maximum number of available airway slots. Revisions to airway slots from the NM may occur at any point between when they’re issued and when you leave the aircraft parking stand. These revisions may be a further delay or an allowance to depart early. Because delays may change at a moment’s notice, it’s best to keep passengers close by (in case you are permitted to depart earlier than originally advised). It’s important to remember that airway slots override airport slots. You do not need to modify airport slots if you receive an airway slot or your airway slot changes.

5. All flights (with some exceptions) are treated equally

Scheduled commercial, charter (non-scheduled commercial), and private non-revenue operators are treated equally in terms of airway slot allocation. It’s a level playing field with a first-come-first-served process. If, however, you have filed a “last-minute” flight plan, you’ll be a lower priority. Medevac and Head of State flights are generally exempt from airway slot requirements but need exemption approval from the NM. Waivers from airway slots are determined on a case-by-case basis, and you must be on a pre-approved list to file a flight plan with a remarks 18 airway slot exempt notation. To secure exempt status, make the application via your civil aviation authority (CAA), who will forward the request to the NM for approval. Please note that your 3rd-party provider cannot assist with this waiver application process.


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Later we’ll discuss managing your slots and dealing with slot delays.

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