GNSS interference report: Russia 2024/2025 – Part 1 of 4: Kaliningrad & the Baltic Sea

Between April and October 2024, especially on October 14, Spire satellite data combined with Polish university sensors documented at least 84 hours of GNSS interference in the Baltic Sea region near Kaliningrad Oblast, Russia. The interference caused position errors exceeding 30 meters, affecting commercial aircraft navigation and maritime traffic across the EEZs of Poland, Lithuania, and Sweden. High-confidence attribution identifies mobile GNSS jamming devices aboard vessels in international waters north-west of Kaliningrad. Satellite telemetry revealed localized full GNSS failures in a maritime hexagon, consistent with shipborne directional jamming. The jamming affected all major GNSS constellations (GPS, GLONASS, Galileo, BeiDou) and impacted aircraft at altitudes up to 36,000 feet. This marks one of the first publicly verified cases of ship-based GNSS jamming in the Baltic Sea linked to Russian EW capabilities associated with the Tobol system. The interference disrupted civil aviation navigation procedures (RNAV approaches), NATO surveillance missions, and commercial maritime routes, elevating operational risks and prompting calls for enhanced space-based interference monitoring by regional stakeholders.