Narrative:

The first officer made an announcement informing us that, in about 20 mins, we would be experiencing bad turbulence. He asked the passenger to remain seated with their seatbelts fastened. He also asked the flight attendants to take their jumpseats. It seemed to have lasted about 30 mins. Because we had forewarning, the flight attendants had enough time to prepare the cabin, and no one was hurt.

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Original NASA ASRS Text

Title: A B777 FLT ATTENDANT COMMENDED THE FLT CREW FOR GIVING ADVANCED NOTICE REGARDING PREDICTED TURB DURING AN OVERWATER FLT.

Narrative: THE FO MADE AN ANNOUNCEMENT INFORMING US THAT, IN ABOUT 20 MINS, WE WOULD BE EXPERIENCING BAD TURB. HE ASKED THE PAX TO REMAIN SEATED WITH THEIR SEATBELTS FASTENED. HE ALSO ASKED THE FLT ATTENDANTS TO TAKE THEIR JUMPSEATS. IT SEEMED TO HAVE LASTED ABOUT 30 MINS. BECAUSE WE HAD FOREWARNING, THE FLT ATTENDANTS HAD ENOUGH TIME TO PREPARE THE CABIN, AND NO ONE WAS HURT.

Data retrieved from NASA's ASRS site as of July 2007 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.