Loss of Positioning, Navigation and Timing (PNT) services

Impact 5
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upper likelihood error bar
risk indicator
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Impact & Likelihood
Impact key
5 Catastrophic
4 Significant
3 Moderate
2 Limited
1 Minor
Likelihood key
5 >25%
4 5-25%
3 1-5%
2 0.2-1%
1 <0.2%


PNT services are a critical component of the UK’s infrastructure. They facilitate a diverse range of essential functions across an increasingly interconnected society. For example, PNT is essential for telecommunications, transport navigation and providing precise timings. A loss of PNT services, either due to technological failures or malicious activity, would have catastrophic and cascading effects across the UK and globally.


The reasonable worst-case scenario is based on a severe technical failure, due to either hardware failure or human error, in a Global Navigation Satellite System constellation leading to data corruption of that service. This would result in inaccurate position and timing data being delivered to users in space and around the world. The compound series of both technical failure and human error means the service would have no choice but to cease operations. There would be a significant disruption or complete cessation of transport (including aviation and maritime services), communications networks, financial services, energy and emergency services within a few hours of the incident taking place. There is also possible further disruption to other space-based services.

Key assumptions

Sectors would revert to older technologies or alternatives to allow for ground services to resume during an extended outage.


Variations include serious and organised crime, jamming and spoofing activities leading to a loss of PNT services, state threat to PNT services, and severe space weather disrupting satellite provision of PNT services. While the impacts are likely to be similar, there would be differences in responses required and the recovery times.

Response capability requirements

Resilient backup systems for critical infrastructure relying on space-based services would be needed, alongside greater space situational awareness nationally and globally.


The restoration of full functionality could take up to several weeks, with some ongoing issues with services. Mitigation includes access to other space satellite services and other sources of PNT.