![Credit: Vic Drosso](https://iims-media-library.s3.eu-west-2.amazonaws.com/wp-content/uploads/2019/03/12143202/Credit-Vic-Drosso.jpg)
The Maritime & Coastguard Agency (MCA) has issued a special safety bulletin to all mariners that use GPS to prepare for a rollover event that will occur on 6 April 2019.
On April 6 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.
Luke Hallett Radio Spectrum Policy Co-ordinator for the Maritime & Coastguard Agency said: ‘If your GPS is more than 10 years old or it’s had no firmware updates then you’re definitely at higher risk of you GPS not working from 6 April. If your GPS falls into either of those categories you need to check with the manufacturer before April 6, otherwise time and position data used for navigation could become inaccurate. It’s important that GPS users check their systems as soon as possible to ensure that they won’t be affected by the impending rollover.’
The MCA’s safety bulletin is intended to help operators understand the implications of the week-number rollover and to take action to ensure all GPS updates are completed.
Read the safety bulletin: GPS_Week_Number_Rollover