The European Union Aviation Safety Agency (EASA) is pleased to announce the publication of the new technical specification ADS-L 4 SRD860 Issue 2, now available under the Downloads section of the ED Decision 2022/024/R.
This latest version of the specification, Issue 2, further advances the Automatic Dependent Surveillance – Light (ADS-L) specification as an acceptable means of compliance for uncontrolled manned aircraft to remain electronically conspicuous when entering U-space airspace. In addition to supporting access to U-space airspace, ADS-L 4 SRD860 is an important enabler for reducing the risk of mid-air collisions and associated fatalities in any airspace, while also facilitating safe drone BVLOS operations outside U-space through improved overall situational awareness and interoperability.
Building on the foundations laid down in Issue 1, which utilises unlicensed frequency bands and uncertified devices, ADS-B 4 SRD860 Issue 2 improves the set of requirements based on experience with initial implementations. It also adds important performance characteristics and introduces a new ground-to-air retransmission capability. Together, these changes support the safe and scalable integration of airspace users within and outside the U-space environment.
The development of ADS-L 4 SRD860 Issue 2 reflects the outcome of extensive collaboration between regulators and industry stakeholders, including device and avionics manufacturers, operators, and user associations. Their contributions were essential to ensuring that the specification remains proportionate, future-proof, and aligned with operational realities.
What is New in ADS-L 4 SRD860 Issue 2
The new issue introduces several important updates and refinements:
- Clarifications and improvements to transmission requirements, incorporating lessons learned and feedback following Issue 1.
- New provisions enabling ground-to-air retransmission of traffic information and other aeronautical data, including hazard notifications, to enhance situational awareness for manned aircraft.
- Cross-reference to the applicable UAS remote identification standard, indicating intention for future expansion of ADS-L applicability to unmanned aircraft operations hence improving interoperability across the entire airspace system.
- Improved network interoperability and forward compatibility by enabling ADS-L 4 SRD860 devices to broadcast their own capabilities.
These enhancements strengthen ADS-L as a practical and interoperable solution supporting the safe coexistence of manned and unmanned aviation in and outside U-space airspace.
Join the ADS-L Coalition
EASA invites interested industry stakeholders, including aviation manufacturers and user associations, to participate in the ADS-L Coalition initiative. This collaborative forum aims to support harmonised implementation, promote innovation, and foster continued alignment between regulators and industry on ADS-L developments.
More information about the ADS-L Coalition and upcoming activities is available here:
https://www.easa.europa.eu/ads-l or https://www.easa.europa.eu/iconspicuity
The text of the ADS-L Coalition Declaration can be accessed here:
https://www.easa.europa.eu/en/downloads/141943/en
EASA encourages stakeholders to review the new specification, Issue 2, and consider the opportunities for engagement as Europe advances on electronic conspicuity to increase safety via enhanced situational awareness for pilots, operators and ground services in any airspace, in a consistent with the deployment of U-space services and the wider integration of new entrants into the airspace.