Take 10 #40: Managing GNSS

Ten top tips for managing GNSS – and the absence of it

WAYPOINT - Staying alert to jamming and spoofing

George Shaw from the Royal Institute of Navigation explores how GNSS can become vulnerable to jamming and spoofing and what mariners can do to stay on course

Who's Navigating? Sailing, shipping and building mutual respect

A love for life on the water led Third Officer Scarlett Barnett-Smith to pursue a rewarding career at sea

WATCHOUT - Loss of GPS leads to groundings, disruption and delay

In this series, we take a look at issues affecting the safety of mariners and the lessons that can be learned from incident reports and examples. The following case studies and analysis have been provided by Gard P&I Club

Taking action

Far from being a theoretical concern, recent incidents in geopolitical conflict zones have underscored the very real and immediate dangers posed by compromised global navigational satellite systems (GNSS).

GNSS jamming

GNSS such as GPS, GLONASS, Galileo and BeiDou are key elements of positioning, navigation and timing. Their signals, however, can be affected not only by unintentional interference but also by intentional jamming. The growing reliance of ships on GNSS means that seafarers need to be aware of how GNSS jamming happens and how to detect it

NavBrief

Do you know where your ship is? Now imagine that the satellite navigation system has failed, and the position is now longer marked on the ECDIS – or is showing as somewhere the ship cannot possibly be. Now what happens?

MARS Report 396 - October 2025

In this bulletin...

202542 A crush on maintenance

202541 Chart plotter mishap

As edited from TAIC (New Zealand) report MO-2024-203

202540 A tripping hazard created

202539 Close call in fog

As edited from SHK (Sweden) 2025-15

202538 Li-ion battery hazards

As edited from USCG Safety Alert 14-25