Narrative:

A momentary overspeed due to sudden onset of wake turbulence occurred at FL380. Airspeed exceedance was 5-7 KTS. Mach .82 did not appear to be exceeded. Aircraft maintenance was notified via dispatch. The above information was entered in the logbook.

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Original NASA ASRS Text

Title: B737-800 Captain reported a slight overspeed as a result of a wake vortex encounter at FL380.

Narrative: A momentary overspeed due to sudden onset of wake turbulence occurred at FL380. Airspeed exceedance was 5-7 KTS. Mach .82 did not appear to be exceeded. Aircraft Maintenance was notified via Dispatch. The above information was entered in the logbook.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.