The European Geostationary Navigation Overlay Service (EGNOS) is the European regional satellite navigation system that is used to improve the performance of global navigation satellite systems (GNSS), such as GPS and Galileo. It has been deployed to provide safety of life navigation services to aviation, maritime and land-based users over most of Europe. EGNOS uses GNSS measurements taken by accurately located reference stations deployed across Europe. All measured GNSS errors are transferred to a central computing centre, where differential corrections and integrity messages are calculated. These calculations are then broadcast over the covered area using geostationary satellites that serve as an augmentation, or overlay, to the original GNSS message. It allows users in Europe and beyond to determine their position to within 1.5 metres, providing also crucial integrity messages regarding the continuity and availability of a signal. The European Commission is the owner of the EGNOS infrastructure. Since January 2014, the exploitation of EGNOS has been fully delegated to the European GNSS Agency (GSA). The future evolution of the EGNOS system (EGNOS v2.x and v3) is under the responsibility of the ESA, as design authority and procurement responsible, supported by industry.

At Airbus D&S Horst contributed to the EGNOS v3 Phase B proposal phase.