THE MARITIME & Coastguard Agency (MCA) issued a special safety bulletin to all mariners that use GPS to prepare for a rollover event that occurred on 6 April 2019,

when navigation data from some older GPS systems might become inaccurate due to the ‘week number’ rollover event.

This could cause stand alone GPS receivers and systems using GPS chips, to produce data that is 19.7 years either in the past or future, therefore generating errors in both the GPS position and time.

However, if onboard equipment has been installed after August 1999, or has regular firmware updates from the manufacturer, there should be minimal risk of an error occurring.