Strike Alert: GPS week rollover

The United Kingdom Maritime Coastguard Agency (MCA) and the United States Homeland Security have issued alerts for operators using Global Positioning System (GPS) for both position and Universal Coordinated Time (UTC).

Both advise that the GPS week number will be rolling over for a second time on 6 April 2019 due to the limitations of the 10-bit binary number, in which the week number is stored. The most vulnerable/exposed units are ones that are more than 10 years and or units that have not been regularly updated.

For more information please see attached safety bulletins from Maritime & Coastguard Agency and Homeland Security.