Beyond Cat-I: EGNOS evolution for aviation safety

10 August 2017
With EGNOS Version 3 augmenting Galileo, it will be capable of delivering performance beyond Cat-I requirements.

EGNOS has revolutionised the way Europe flies. As an alternative to ground-based Instrument Landing Systems (ILS), EGNOS utilises geostationary satellites and a network of ground stations to receive, analyse and augment GPS signals. The resulting EGNOS LPV 200 service provides vertical guidance that enables aircraft to reach a decision height as low as 200 feet – a capability similar to what is provided via ILS Cat-I but without the financial burden of installing, maintaining and calibrating ground equipment.

Although this accomplishment is impressive as is, EGNOS is just getting started. 

EGNOS Version 3, set to enter service in the near future, will augment both GPS and Galileo. As a result, it will be capable of delivering performance beyond Cat-I requirements. Not only will this capability increase performance and improve accuracy, resilience and safety, it will also enable the aviation sector to design new EGNOS-based services and applications.  

To help user in this next generation of EGNOS, the European Commission, Directorate-General for Internal Market, Industry, Entrepreneurship and SMEs (DG GROWTH) is set to publish a call for a new service contract. The scope of the contract includes:

  • Analysing aviation needs and identifying opportunities for new services that go beyond Cat-I and are enabled by EGNOS’ dual frequency augmentation of GPS and Galileo;
  • Identifying user needs, such as an evolution towards Cat-II approach procedures, or new services, all within the framework of a future integrated communication, navigation and surveillance (iCNS) system;
  • Analysing  potential service improvements versus existing services;
  • Assessing safety requirements and their potential impact on both EGNOS and aviation user receivers;
  • Reviewing service provision constraints. 

The contract notice will be published in the near future. More information can be found in the Prior Information Notice (PIN). 

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Updated: Sep 25, 2017