Narrative:

Approximately 15-20 minutes after entering cruise phase of flight while lying in the crew rest facility (bunk) our flight encountered a severe turbulence event. We were flying in smooth air and started getting a little bit of chop which was quickly followed by a moderate turbulence jolt. The captain announced over the PA for the flight attendants to take their seats and almost immediately after that we encountered severe turbulence. It was an extreme jolt. It was like being slammed to the ceiling and then slammed back down to the ground. 5 fas were injured in the aft galley and I sustained injuries in the lower bunk. Even though I had my seatbelt on I hit my head against the ceiling; my shoulder got jammed against the notch on the side of the bunk (certain lower bunks have a bump out on the left side of the bunk); and hurt my back due my waist remaining on the bunk while my legs and upper torso did the flailing. I was temporarily stunned but remained awake. At the time my head hurt somewhat but felt lucky that the turbulence had not continued longer. I believe had it lasted longer I would have sustained significant injuries. However; the event was over. At the time everybody; including me; felt good enough to continue so we proceeded to our destination. During my layover my back stiffened up but I was able to perform my duties on the return leg so I performed my duties as a relief pilot [for the return].

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Original NASA ASRS Text

Title: B777 First Officer reported being injured by severe turbulence while lying in the crew rest bunk with his seat belt fastened. Several flight attendants were also injured in the main cabin.

Narrative: Approximately 15-20 minutes after entering cruise phase of flight while lying in the crew rest facility (bunk) our flight encountered a severe turbulence event. We were flying in smooth air and started getting a little bit of chop which was quickly followed by a moderate turbulence jolt. The captain announced over the PA for the Flight Attendants to take their seats and almost immediately after that we encountered severe turbulence. It was an extreme jolt. It was like being slammed to the ceiling and then slammed back down to the ground. 5 FAs were injured in the aft galley and I sustained injuries in the lower bunk. Even though I had my seatbelt on I hit my head against the ceiling; my shoulder got jammed against the notch on the side of the bunk (certain lower bunks have a bump out on the left side of the bunk); and hurt my back due my waist remaining on the bunk while my legs and upper torso did the flailing. I was temporarily stunned but remained awake. At the time my head hurt somewhat but felt lucky that the turbulence had not continued longer. I believe had it lasted longer I would have sustained significant injuries. However; the event was over. At the time everybody; including me; felt good enough to continue so we proceeded to our destination. During my layover my back stiffened up but I was able to perform my duties on the return leg so I performed my duties as a Relief Pilot [for the return].

Data retrieved from NASA's ASRS site 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.