Britain’s railway has taken a significant step towards next-generation positioning systems, with quantum navigation technology now being tested on the national network for the first time.
The development centres on quantum inertial navigation, a system that uses ultra-sensitive sensors to measure movement and rotation with exceptional accuracy. Unlike GPS, it operates independently of satellite signals, offering a potential solution in areas where traditional navigation struggles, such as tunnels, dense urban environments or locations affected by interference.
Moving beyond GPS limitations
The technology is being explored as a future alternative to conventional trackside positioning infrastructure, which can be expensive to install, maintain and protect from failure.
By removing reliance on external signals, quantum navigation could provide a more resilient and potentially lower-cost approach to train positioning, with implications for signalling, operations and maintenance.
A key milestone has now been reached, with a Rail Quantum Inertial Navigation System (RQINS) tested on a live mainline service. The system was installed on a Great Northern train operated by Govia Thameslink Railway, running between central London and Welwyn Garden City on 3 March.
The trial has generated real-world operational data, helping engineers understand how the technology performs in a complex, live railway environment.
From concept to operational potential
The programme builds on earlier work undertaken by the Ministry of Defence and trials on Transport for London’s network, marking a transition from controlled environments to heavy rail deployment.
Development is being led by a consortium headed by MoniRail, working alongside Imperial College London, the University of Sussex, QinetiQ, PA Consulting and the National Physical Laboratory, with support from Innovate UK and the Department for Science, Innovation and Technology.
The initiative is coordinated by GBRX, the innovation arm supporting Great British Railways, with a focus on accelerating the adoption of advanced technologies across the network.
Rail Minister Lord Hendy said: “For more than two centuries Britain’s railway has forged technologies that have shaped the modern world. The development of quantum inertial navigation continues that legacy. With these new capabilities, we’re preventing equipment failures, helping to boost our railway’s reliability and keeping passengers moving.
“It’s all part of our plan to modernise track and train under Great British Railways, adopting world-leading technology that increases resilience to improve passenger experience while supporting jobs, growth and homes.”
A platform for wider transformation
Beyond positioning, the implications of quantum sensing extend into multiple areas of railway performance.
Toufic Machnouk, Managing Director of GBRX, said:
“Developing new technologies within the complexity of a railway network is essential to understanding how frontier technologies can be translated into operational capability.
“Quantum sensing is one of the UK Government’s frontier technological priorities. Railways, as one of the country’s most complex operational systems, provide a powerful platform for developing and scaling these capabilities for rail and beyond.
“This programme begins the process of understanding how quantum positioning could fundamentally reshape how railways work. In the future, it could reduce reliance on costly trackside positioning systems while enabling new capabilities for signalling, improved operational performance, network planning, enhanced condition monitoring and more intelligent railway operations.
“This test represents an early but important step in that development journey and demonstrates how collaboration between government, academia and industry can accelerate the development of frontier technologies.”
What it means for the industry
For rail operators and suppliers, the direction is clear. Positioning systems are moving towards onboard, data-driven solutions, reducing dependency on fixed infrastructure.
If successfully developed and deployed at scale, quantum navigation could:
- Improve reliability in challenging environments
- Reduce infrastructure and maintenance costs
- Enable more flexible and advanced signalling systems
- Support wider digital railway ambitions
This remains an early-stage trial, but it signals something more significant. The railway is no longer just adopting proven technologies; it is becoming a testbed for frontier innovation, with the potential to reshape how the network is operated for decades to come.
