Surveillance optimisation

At EUROCONTROL, we work with our stakeholders to optimise surveillance infrastructure as part of our larger surveillance domain activities.

We monitor and support the operation, evolution and sustainability of surveillance infrastructure and its applications in the European air traffic management (ATM) network.

We support synergies, integration and the rationalisation of infrastructure in the surveillance domain and with other systems to achieve cost and spectrum efficiency, while supporting operational excellence through a holistic, cross-domain, network perspective.

We provide support for the implementation of EU Regulation 1207/2011 on Surveillance Performance and Interoperability Implementing Rule (SPI-IR) in cooperation with European Union (EU) institutions and stakeholders.


Our objective is to improve network performance and ensure global interoperability using an optimal mix of Mode S, multilateration, ground- and space-based ADS-B and non-cooperative surveillance.

We aim to optimise the use of surveillance data in Europe, enabling the performance needs with cost and spectrum efficiency.

Our contribution

We provide surveillance implementation support to stakeholders and so contribute to achieving the European ATM Network performance objectives.

In this context, we publish:

  • implementation monitoring plans and reports;
  • specifications;
  • guidance material;
  • evaluation reports.

EU Regulation SPI IR

We support our stakeholders on the implementation of the EU regulation 1207/2011 (SPI IR) and its amendments.

We cooperate with European Union Aviation Safety Agency (EASA) on various topics such as the production of acceptable means of compliance and guidance material for the EU Regulation SPI IR.


Furthermore, our long-standing ADS-B activity addresses our stakeholders’ needs in a comprehensive end-to-end approach, including operational, technical, planning and business aspects.

We report on surveillance equipage monitoring, such as the ADS-B airborne equipage evolution and the implementation progress monitoring on a periodic basis.


At EUROCONTROL, we co-lead and support performance based surveillance (PBS) in close cooperation with our stakeholders and the International Civil Aviation Organization (ICAO).


In the context of PBS, we deliver the European specification of surveillance system performance (ESASSP), which is used by the stakeholders for the demonstration of compliance of their surveillance system. A new version of this document is currently being prepared and will be available for public consultation soon.

We also co-lead and contribute to the standards and specifications for surveillance avionics, ADS-B ground stations, multilateration systems, independent non-cooperative surveillance, etc, in cooperation with EUROCAE and RTCA.

We develop the European Mode S specification (EMS). A new version of this document is currently being prepared and will be available for public consultation soon.

Use of downlink aircraft parameters (DAPs)

We aim at maximising the use of surveillance (ground, airborne and space-based) including aircraft derived data (ADD) or downlinked aircraft parameters (DAP) in order to increase the benefits from the stakeholder investments. This is supported by the sharing of best practices by our stakeholders.

Support to SESAR

We contribute to SESAR projects since the start of this programme, in areas such as surveillance strategy and roadmap, PBS, ADS-B, rationalisation, security etc.


The modernisation process of Surveillance systems started in the early 2000s and included the transition from SSR Mode A/C to SSR Mode S technology, implementation of multilateration systems and ADS-B as well as the use of state-of-the-art surveillance data processing and evaluation systems. EUROCONTROL has coordinated and supported this process since the beginning with relevant activities such as the Mode S programme, CASCADE programme (ADS-B and multilateration), etc.

The cornerstones for network performance improvements are Mode S and ADS-B airborne equipage combined with a cost and spectrum efficient ground (or space)-based surveillance infrastructure (optimal mix of sensors).

Key inputs to this activity are the results of monitoring 1030/1090 MHz radio frequency bands and surveillance avionics, as well as progressing the implementation of ground Surveillance products.

Working arrangements

The stakeholder coordination on the Surveillance optimisation work is performed by the Network Surveillance User Group (NSUR), which reports to the Surveillance Steering Group (SUR-SG).

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