GNSS resilience is an economic and security priority

Modern society has become profoundly reliant on Global Navigation Satellite Systems (GNSS). These systems support aviation safety, emergency services, finance, communications, energy networks and an expanding array of autonomous and industrial systems. Yet despite this reliance, GNSS remains inherently fragile: low‑power signals transmitted from medium Earth orbit are surprisingly easy to degrade, and the consequences of disruption can be severe.

Disruption arises from multiple sources including natural phenomena such as solar flares, technical anomalies within satellite constellations and malicious interference — the latter of which is on the rise. According to the International Air Transport Association, deliberate GNSS interference now affects more than 5% of commercial flights within Europe, with a 220% increase in signal-loss events reported between 2021 and 2024. Recent incidents, such as the interference that affected European Commission President Ursula von der Leyen’s aircraft, highlight the very real risks posed by malicious activity.

Much of the public discussion on GNSS focusses on its role in positioning and navigation, yet its timing function is equally vital. Sub‑microsecond timing accuracy is essential for modern society, enabling synchronised power grids, resilient broadcast and cellular networks, accurate timestamped high-frequency financial trading and reliable industrial automation. Systems that rely exclusively on GNSS for timing are increasingly vulnerable to disruption, whether through accidental outages or deliberate interference.

This challenge becomes more acute during major international events. Large gatherings of global leaders such as the World Economic Forum, G20, NATO Summit or COP31 concentrate diplomatic, political and security activity into a single location amplifying the consequence of targeted disruption.

Detecting and mitigating disruption

As awareness grows, attention is shifting toward real‑time detection and layered resilience. Modern assurance systems can monitor GNSS signal integrity continuously, comparing it against diverse sources from inertial sensors and atomic clocks through to terrestrial radio systems and other complementary technology. These multi‑sensor approaches can provide early warning of jamming, spoofing and anomalous behaviour before they cascade into operational failures. Crucially, they can allow aircraft, vehicles or critical infrastructure to transition gracefully to independent backup sources when GNSS cannot be trusted.

If resilience is weak, the consequences are profound. Disruption during a period of elevated security for example, when multiple heads of state are present, could impede air traffic coordination, delay decision‑making or introduce uncertainty into command-and-control systems. Such effects need not be catastrophic to be destabilizing; even small degradations can create confusion in crowded airspace, delay decision making, strain emergency services or undermine confidence in critical systems.

A coordinated, cross-sector response is therefore essential. Defense, aviation, telecommunications, energy and cybersecurity communities each hold part of the solution. A layered approach, combining GNSS with independent timing sources, terrestrial navigation aids, inertial systems and persistent interference monitoring provides the robustness necessary to maintain continuity in contested environments. Clear protocols for switching to fallback modes, and shared situational awareness across sectors, are equally important.

The art of (modern) war 

At the same time, the character of conflict has evolved across both active combat and sub‑threshold activities. The electromagnetic spectrum is now treated in United Kingdom defense strategy as a military domain in its own right, shaping everything from electronic warfare and cyber operations to space‑based effects. These capabilities appear not only in high‑intensity operations but also in the hybrid activities that sit below the threshold of open conflict. GNSS jamming and spoofing span this full range: they are established tools in contested warfare, yet also increasingly feature in sub‑threshold behavior that disrupts civil and military systems without the overt use of physical force.

Against this backdrop, the urgency of GNSS resilience becomes clear and many governments are now modelling and stress-testing the economic consequences of GNSS outages. The U.K., for example, has estimated that a nationwide disruption lasting just 24 hours could cost more than 1.4 billion pounds ($1.9 billion), before accounting for secondary effects across digital services, logistics and financial markets. This, in turn, is driving renewed investment in sovereign position, navigation and timing technology, terrestrial backups and advanced monitoring technologies able to detect and respond to anomalous activity in real time.

As reliance on high‑accuracy positioning and timing deepens across critical infrastructure and digital services, the resilience of satellite‑derived PNT is becoming a central strategic concern. Major global events may draw attention to this dependence, but the challenge is continuous and extends across every sector of the modern economy.

Some nations are pursuing sovereign alternatives and national backup systems; others lean on alliances, shared infrastructure or emerging commercial services. Yet the interconnected nature of global transport, finance and communications means that GNSS disruption rarely respects borders. Building resilience is therefore not merely a national priority but a collective one requiring cooperation, common standards and trusted civilian–military partnerships.

The question is no longer whether major GNSS disruption will occur, but how prepared will we be?

Aled Catherall is the Chief Technology Officer at Plextek.

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