Man sailing

Safety bulletin for mariners who use GPS

Samantha shares this latest news on behalf of the Maritime & Coastguard Agency (MCA). Ed


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.

Be aware of possible errors
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.

Who is at higher risk
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 your 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.”

Find out more
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.

For more information on the rollover event please visit the GPS safety bulletin

Image: © Vic Drosso