Global shipping has entered a precarious and unstable era. Rising geopolitical tensions in key maritime corridors, including threats from Iran to target vessels transiting strategic waterways and the disruption of energy and export routes, are reminding the industry that the seas carrying the world’s trade are not always predictable.
Alongside these developments, operational and commercial decision making is becoming more sensitive to how risk is assessed and understood. It is not only the presence of threat that matters, but the level of confidence operators and stakeholders have in the data used to navigate and manage it.
But despite the dangers, there are mitigations. Indeed, few technologies have reshaped maritime navigation as completely as satellite positioning. Over the past three decades Global Navigation Satellite Systems (GNSS) have moved from specialist navigation tools to the backbone of modern maritime operations. They now support everything from deep sea route planning to dynamic positioning and complex port approaches.
That success has encouraged a widespread assumption across the sector that satellite signals will always be available and reliable. Recent events suggest that assumption is becoming harder to defend. And this is where APNT enters the equation, providing greater confidence in vessel positioning and supporting more informed risk planning.
Disruption affecting GNSS is now being reported with increasing frequency in areas that matter most to international shipping and naval activity. Interference incidents across the Black Sea, the Baltic and parts of the Eastern Mediterranean have demonstrated that vessels can suddenly encounter unreliable or manipulated navigation signals. Ships operating in these regions have reported positions shifting unexpectedly or appearing many miles from their true location. For crews navigating congested waters or preparing to enter busy ports this creates real uncertainty.
Alastair McLeod, CEO, Ground Control
These incidents are often occurring along strategically sensitive shipping routes where commercial vessels, naval forces and energy exports converge. As maritime trade routes become more contested, the reliability of the navigation systems that guide vessels through them is coming under increasing scrutiny.
The operational implications
Reliable positioning and timing sit at the centre of modern maritime activity. Commercial vessels rely on accurate PNT data for electronic charts, automated safety systems, route optimisation and offshore operations. Defence platforms depend on the same signals to coordinate manoeuvre, maintain situational awareness and synchronise communications. As shipboard systems have become increasingly digital and interconnected, reliance on satellite positioning has expanded well beyond navigation itself.
When disruption occurs along major trade routes the implications extend beyond navigation safety. Tanker movements, container traffic and energy supply chains all depend on predictable maritime operations. Uncertainty about a vessel’s position in contested waters can quickly ripple through global supply networks. It can also make it more difficult to assess exposure with confidence, leading to more cautious operational decisions and a greater reliance on assumption where verified data is limited.
This growing dependence means that disruption to GNSS can quickly affect multiple operational systems at once. A degraded or manipulated signal does not simply alter a position fix on the bridge. It can also introduce uncertainty into automated systems that rely on the same underlying timing and location data. In an environment where maritime operations are increasingly data driven; the integrity of that information becomes just as important as its accuracy.
From reliance to resilience
For the maritime sector, the question is no longer whether satellite navigation is essential. Its role in modern operations is firmly established. The challenge is how to ensure vessels can continue to navigate safely and confidently when satellite signals are disrupted or their integrity is uncertain. Addressing that challenge requires a shift in thinking from reliance on a single positioning source to a more resilient approach to navigation.
APNT applies a long-standing maritime principle. Reliable navigation comes from comparing information from multiple sources rather than depending on a single instrument. In a modern digital environment this means combining GNSS with complementary systems capable of supporting or validating positioning and timing data.
A layered navigation architecture
An APNT approach typically integrates several independent sources of positioning information. Complementary satellite signals, inertial navigation systems, terrestrial inputs and alternative timing references can all contribute to a layered navigation architecture in which each element strengthens the resilience of the whole. When these systems are integrated effectively, onboard technology can identify anomalies in satellite signals and maintain situational awareness even if one component becomes unreliable.
Defence organisations have long recognised the importance of this approach because operating conditions cannot always guarantee uncontested access to satellite navigation. In contested environments degraded or denied GNSS is treated as a realistic operational scenario rather than a rare technical failure. That reality has driven investment in resilient navigation systems capable of preserving operational capability when primary signals are disrupted.
A shared challenge for shipping and defence
Commercial maritime operators are increasingly encountering circumstances that echo those concerns. Interference around major ports, congested radio environments and disruption linked to geopolitical tensions demonstrate that satellite signals can be affected by factors beyond the control of ship operators. Recent threats to commercial shipping in strategic waterways show how quickly navigation risks can become tied to wider security and energy supply concerns.
For vessels navigating busy trade routes or approaching complex harbour infrastructure, the ability to verify positional information has therefore become an important part of operational risk management. Greater confidence in that data not only supports safer navigation but also underpins more informed decision making in environments where uncertainty is becoming a defining factor.
The maritime industry has repeatedly adapted its navigation practices in response to changing operational realities. Celestial observations gave way to terrestrial radio aids, which were eventually complemented and largely replaced by satellite positioning. The growing focus on APNT reflects the next stage in that evolution. The priority shifts from simply obtaining a position to ensuring that the position being used can be trusted.
Satellite navigation will remain fundamental to maritime operations for the foreseeable future, yet resilience must increasingly be built around those signals rather than assumed. By combining satellite positioning with complementary sources of navigation and timing data, the sector can maintain confidence in the information guiding vessels even when signal conditions are less predictable.
As maritime activity becomes more connected, more automated and in some regions more strategically contested, the ability to confirm the integrity of positioning information will become just as important as the accuracy of the position itself.
Source: By Alastair McLeod, CEO, Ground Control
