However, EASA said, tests of some GPS devices revealed that not all manufacturer implementations will correctly handle the April 6 rollover. The EASA bulletin is intended to help operators understand the implications of the week-number rollover and recommend steps to rectify the issue.
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So far, the only reported issues have been with Honeywell GPS systems...so far.
Add: BOM weather balloons grounded due to rollover. BOM said its equipment supplier advised the bureau of the fault after the rollover on April 7, and balloon launches ceased on April 8.
A Shanghai Airlines 787 was also reportedly affected.