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Old 12th Apr 2019, 13:15
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eppy
 
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Originally Posted by GordonR_Cape
More like an early version of the Unix year 2038 rollover problem: https://en.wikipedia.org/wiki/Year_2038_problem
GPS rollover is not directly related to Y2K or the Unix year 2038 problem, but the underlying concept is the same.

The GPS standard has 10 bits of data for the date which is only enough for around 20 years. The last rollover was in 1999.

When unpatched GPS units rolled over to 000000000 on 8th April, the date showed as 1999. The Honeywell service bulletin below explains it well. The standard has now been updated to 14 bits of data so we won't have to worry about this again for a few hundred years.

https://aerospace.honeywell.com/en/news-listing/2019/march/service-information-letter-briefing-gps-week-rollover
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