Air navigation obstacles

Obstacles to aviation are installations such as buildings, antennas, towers, cranes, cable cars, wind turbines, high-voltage power lines, cranes and construction machinery, etc., but also plants (especially trees) that may pose a hazard to aviation because of their location or height. To ensure safety in aviation, such installations and plants must be registered and publicised before they are erected. Some must be marked or lit and those requiring a permit must undergo a special inspection.

Air navigation obstacles must be registered via the Aviation Data Collection System (DCS).

Brief overview

An object is classed as an air navigation obstacle in a built-up area if it is 60 metres tall or more and in a non built-up area if it is 25 metres tall or more. Specific regulations also apply in areas around aerodromes and helicopter landing sites. Owners must register the object or have it authorised by the FOCA. Details are set out in Article 63 ff. of the Ordinance on Aviation Infrastructure (AvIO, SR 748.131.1).

Objects must be registered on the Aviation Data Collection System (DCS) portal. The DCS portal allows owners to determine during the registration process the extent to which the reported object really constitutes an air navigation obstacle, whether further requirements such as marking or lighting are necessary or even whether an aviation-specific inspection including authorisation is required.

When an installation requires authorisation, the FOCA considers air navigation safety and which safety measures, such as marking and/or lighting, are to be taken. All current air navigation obstacles outside aerodromes are published on an online map on the Confederation's geoportal. This is updated daily. It can be also found in the official aviation publications according to applicable publication cycles.

Determining whether an object is an obstacle to air navigation

Is the object 25 metres tall or more in a non built-up area or 60 metres or more in a built-up area?
You must register the object on the DCS portal.

Is the object 100 metres tall or more?
A permit from the FOCA is required. The same applies to wind turbines, high-voltage power lines and slacklines at 60m or above. You can register the obstacle and obtain a permit on the DCS portal.

Is your object located within an aerodrome's obstacle limitation surface (OLS) or in the vicinity of a helicopter landing site?
In this case, a permit from the FOCA is also required. Plants (especially trees) can also penetrate the OLS as they grow and thus pose a danger to aviation. You can register the obstacle and obtain a permit on the DCS portal.

Not sure?
Play it safe, because you are responsible and liable in the event of damage! The DCS portal allows owners to check when registering whether the reported object really constitutes an air navigation obstacle, whether further measures such as marking or lighting are necessary or even whether an inspection and authorisation are required.

Have you spotted an air navigation obstacle?
Pilots are required to update the navigation systems periodically and to keep themselves informed about changes to obstacles.

They should also notify the FOCA of any installations they have spotted that are not included in current publications or which appear incorrectly, or whose marking or lighting appears to be inadequate. This can be done via Pilot obstacle report, providing as precise details as possible.