Important change to take effect on April 6

The UK’s Maritime & Coastguard Agency (MCA) has issued a special safety warning to mariners regarding the use of GPS equipment, especially if it is more than 10 years’ old or has had no firmware updates.

The MCA bulletin for all mariners that use GPS informs them to prepare for a rollover event that will occur on April 6, 2019. On that day navigation data from some older GPS systems might become inaccurate due to the ‘week number’ rollover event.

The MCA suggests that this could cause stand-alone GPS receivers and systems using GPS chips to produce data that is from 19.7 years in the past or in the future, 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 MCA, says: “If your GPS is more than 10 years’ old or it has had no firmware updates, then you’re definitely at higher risk of your GPS not working from April 6. 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,” he adds, “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.