ADS-L in Switzerland: guide for pilots

ADS-L is one of the perceptibilité électronique technologies available to pilots, alongside FANET / FANET+, FLARM andADS-B. These are not synonyms: each addresses a different use, and a device can combine several of them. Compare all technologies.

ADS-L (Automatic Dependent Surveillance – Light) allows an equipped aircraft to transmit its position by radio, so it can be detected by other aircraft equipped with a compatible receiver. See our complete ADS-L guide.

Swiss airspace is shared by many categories of aircraft, often flying at low altitude in mountainous areas. Electronic perceptibility aims to reduce blind spots between aircraft that do not always see each other easily with the naked eye.

Current status communicated by the authorities:

The FOCA has detailed in writing the envisioned implications by category, for manned aircraft flying VFR in class G and E airspace: paragliders and hang gliders — ADS-L Out transmission, reception to be considered depending on the device; gliders and balloons — two distinct components: the envisioned extension of the transponder requirement (art. 29 ORA) on one hand, and electronic perceptibility via ADS-B Out or ADS-L Out on the other (a Mode S transponder alone is not sufficient to fulfill this second component), with maintaining or upgrading existing equipment including FLARM recommended; light motorized aircraft — already applicable transponder obligations to be maintained, ADS-B Out and an additional ADS-L In/Out recommended for any new equipment. These implications are not yet a legally binding obligation in force.

Yes. The FOCA indicates that paragliders and hang gliders should be equipped with an ADS-L device as part of the future obligation — and already recommends, on a technical basis, this equipment today. See our guide ADS-L for paragliding.

No, there is no guarantee that it helps avoid a collision: ADS-L is an electronic perceptibility tool complementary to visual vigilance, not an autonomous collision avoidance system. The ADS-L function alone does not detect aircraft that do not transmit this protocol (some multimode devices may however also receive other protocols such as ADS-B), and it makes no decision on behalf of the pilot. Its messages nevertheless contain the elements necessary to build an alert function comparable, in its purpose, to that of FLARM — technical feasibility validated by the OCAP project (Open Collision Avoidance Protocol), supported by the FOCA. This does not certify equivalence with FLARM nor guarantee that a given commercial product already implements it: check the functions actually confirmed on each product sheet.

ADS-B is the standard used by commercial aviation and a large part of general aviation. ADS-L is a distinct protocol, optimized for low-cost, low-power equipment, designed for aircraft with little onboard electronics. Details in our comparison ADS-L vs ADS-B.

FLARM is a proprietary system widely used in gliders. ADS-L is a distinct, more recent technology. Details in our comparison ADS-L vs FLARM.

Broadcasting one's position makes an aircraft perceptible by other aircraft equipped with reception. This is the simplest function to implement and often the most economical.

Reception allows you to perceive equipped aircraft around you, generally displayed on a screen. This is a function complementary to broadcasting, not systematically included in all devices.

Each FlyVisible product page clearly displays the device's ADS-L broadcast and reception capabilities. See also our guide ADS-L compatibility.

A standard smartphone is generally not, on its own, an ADS-L device in the strict sense. See our guide smartphone and ADS-L.

No obligation requires immediate equipment. Equipping yourself early allows you to become familiar with the technology without urgency. Check our configurator to identify equipment suited to your practice.

Yes, for certain devices. The Confederation financially supports the purchase of Skytraxx and XC Tracer models via the Variosubvention program (~CHF 72.- per device), for which the application is submitted directly on variosubvention.ch after purchase. See our guide federal subsidy for an ADS-L device.