On the night of June 15, 2025, the oil tanker Front Eagle transmitted a series of impossible positioning signals – at one moment jumping dozens of miles in seconds. Soon after, it collided with another tanker near the Strait of Hormuz, which caught fire.
According to a Financial Times visual analysis, at least 170 ships transiting the same choke point during a two-hour window showed scores of sudden position “jumps” – the tell-tale signature of GNSS spoofing. The incident has reignited debate about the rising threat of electronic interference in global shipping, especially in regions where geopolitical tensions are high.
This GNSS interference heat map shows real-time jamming and spoofing events from the Middle East to East Asia. The same emitters that rattle airliners also wash over busy sea lanes. Though indeed problematic for aviation, cyberattacks are arguably more consequential when it comes to shipping. That affects everything from supply chains and oil prices to the risk of major environmental disasters.
Timing: The foundation of GNSS and a growing point of vulnerability
When we think of GNSS/GPS, the image that comes to mind is a pulsing dot on a map, perhaps moving along a pre-plotted route. To a receiver on the ground, GNSS is a series of precise timestamps beamed from different satellites that arrive a billionths of a second apart. These signals are then used to calculate the latitude and longitude data we see represented in graphical format on our screens. However, when a GNSS jamming device or technology that counterfeits (spoofs) timestamps is used nearby, map positions can suddenly disappear or become wildly inaccurate.
Fixing GPS vulnerability with timing you can trust
In a recent blog post, we highlighted the growing importance of backup timing for the aviation industry. It is equally, if not more urgent, that global shipping adopts many of the same solutions. Vessels can even be fitted with enhanced primary reference time clocks (ePRTCs) that teach bridge devices to prioritize that timing source over satellite signals alone. While ePRTCs don’t replace GNSS navigation, they provide a stable time base that supports alternative navigation methods when satellite signals are compromised, helping ships maintain a smooth and reliable track line.
What’s more, the same solution functions as an alarm. When a GNSS message claims a microsecond has passed but the ship’s clock says it was only half that, receivers can reject the data before it reaches the helm. Ships don’t appear to teleport around the map and Automatic Identification System (AIS) messages remain readable.
When GNSS falters, ePRTCs kick in with a stable time base for alternate navigation.
Follow these steps to combat GNSS interference in shipping lanes
- Install an ePRTC: Use a cesium clock paired with a multi-band GNSS receiver to deliver nanosecond-level accuracy for extended periods when satellite input is unavailable or unreliable.
- Blend timing sources: Feed the clock with GNSS when it’s clean, and PTP over port fiber when docked. Oscilloquartz technology also enables ePRTC operation using trusted phase sources like PTP – even when satellite signals are unavailable.
- Train for timed failover: During routine drills, block GNSS input to the ePRTC for ten minutes to ensure ECDIS, AIS and radar overlays stay in sync. If they do, the ship is well protected.
The digital-age equivalent of a spare compass
Roughly 20% of the world’s oil flows through the Strait of Hormuz. Whether one or both vessels involved in the recent collision in the area were misled by spoofed signals or simple human error, the lesson is the same: a resilient timing layer helps reduce the chances of disasters occurring.
Threats to navigation in some of the world’s most important commercial waterways are growing, but thankfully, effective countermeasures do exist. For more information about how our comprehensive portfolio of timing and synchronization solutions helps safeguard maritime systems when GNSS fails, visit oscilloquartz.com.