Coast Guard Warns on GPS Jamming

The U.S. Coast Guard has issued Marine Safety Alert 01-16 to warn mariners of the potential detrimental impact to navigation caused by GPS interference or jamming. The warning emphasizes the importance of understanding how vessel equipment could be impacted by the loss of a GPS signal.

The Coast Guard states that this past summer, multiple outbound vessels from a non-U.S. port suddenly lost GPS signal reception. The net effect was various alarms and a loss of GPS input to the ship’s surface search radar, gyro units and ECDIS, resulting in no GPS data for position fixing, radar over ground speed inputs, gyro speed input and loss of collision avoidance capabilities on the radar display. 

Fortunately, the vessels were able to safely continue theirvoyage using radar in heads up display, magnetic compass and terrestrial navigation. Approximately six nautical miles later, the vessels’ GPS units resumed operation. Although the vessels had back-up systems to allow a safe transit, the consequences could have been severe, warns the Coast Guard.

The alert is available here.