Narrative:

Encountered unexpected; abrupt; momentary moderate turbulence. Airplane and flight conditions: had reached cruise altitude and been established for a few mins. Seatbelt sign had been turned off after established in cruise; and a few mins prior to incident. In clear air; with some cirrus above; and undercast/broken well below. Ride was smooth to nearly smooth with very minor nibbles; both just prior to and immediately after the turbulence encounter. Turbulence information: during discussion with dispatch earlier; we were informed of light and moderate turbulence at FL360-FL380 (our normal cruise altitudes) as well as moderate reports during climb 12000 ft to FL270. ATC did have some information; but not complete information. I can't remember if they actively stated that FL320 was 'a good ride;' or if they didn't have any active 'bad' turbulence ride reports; but the higher altitudes seemed worse in any case. We planned (on the ground) for and requested (in the air) FL320. During climb; we did not hit the forecast/reported moderate turbulence; encountering only light turbulence in a couple of spots; and light chop to smooth elsewhere. Even though it was fairly smooth during the upper climb; I kept the seatbelt sign on until after reaching cruise. Turbulence incident: near abeam mli/mzv; we encountered a momentary moderate turbulence; or jolt. It seemed like just one. Very short duration. I don't recall any negative forces; just a very positive jolt. Nothing to my knowledge moved in the cockpit; even open drinks in the cockpit did not spill. Shortly after; the purser called to inform us of multiple injuries; the worst of which seemed to be a passenger head gash; with 'lots' of blood. The cabin at this point started addressing the injuries with recruitment of a medical doctor passenger; accessing first aid kits; and cabin clean-up. We informed ATC of the encounter and started the process of a diversion through ATC and dispatch. It seemed to take a long time to start getting accurate information from the cabin; as well as coordinating with dispatch. In actuality; it probably went pretty quickly and efficiently. We had an offline jumpseater; who we sent to the cabin to start gathering detailed information on injuries. He was a great resource and helped a lot. I suppose it seemed like a long time because I still didn't have any information whether or not any injuries were life threatening and what our divert decision needed to be. We finally did start to get information that none of the injuries were life threatening. I had it confirmed a second time as well. We coordinated with dispatch and decision to continue to lax was made; considering airports along route for possible diversion if status of injuries deteriorated. Further information from cabin showed 3 passenger injuries -- the head laceration; and other bumps and bruises; and 3 flight attendants injured knees and ankle. All but 1 flight attendant continued working; as well as one flight attendant jumpseater also volunteered to work. We discussed the intensity of the encounter and decided that it was moderate. We considered a severe declaration; but there was no airplane loss of control; nor any observed altitude or attitude deviations; no moving objects or spilled drinks in the cockpit. The cabin did experience some passenger and flight attendants falling down; and some galley items falling. Since the conditions were favorable just prior to the event; a lack of preparedness may have been the reason for the multiple injuries. Also; considering the intensity call; ATC did query us a number of times if it was severe; or about the turbulence severity. I do not think I termed it severe; but in the heat of the moment; I do not know. Afterward; we attempted to clarify it as moderate.

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Original NASA ASRS Text

Title: B777 FLT CREW ENCOUNTERS MODERATE TURB RESULTING IN SEVERAL INJURIES.

Narrative: ENCOUNTERED UNEXPECTED; ABRUPT; MOMENTARY MODERATE TURB. AIRPLANE AND FLT CONDITIONS: HAD REACHED CRUISE ALT AND BEEN ESTABLISHED FOR A FEW MINS. SEATBELT SIGN HAD BEEN TURNED OFF AFTER ESTABLISHED IN CRUISE; AND A FEW MINS PRIOR TO INCIDENT. IN CLR AIR; WITH SOME CIRRUS ABOVE; AND UNDERCAST/BROKEN WELL BELOW. RIDE WAS SMOOTH TO NEARLY SMOOTH WITH VERY MINOR NIBBLES; BOTH JUST PRIOR TO AND IMMEDIATELY AFTER THE TURB ENCOUNTER. TURB INFO: DURING DISCUSSION WITH DISPATCH EARLIER; WE WERE INFORMED OF LIGHT AND MODERATE TURB AT FL360-FL380 (OUR NORMAL CRUISE ALTS) AS WELL AS MODERATE RPTS DURING CLB 12000 FT TO FL270. ATC DID HAVE SOME INFO; BUT NOT COMPLETE INFO. I CAN'T REMEMBER IF THEY ACTIVELY STATED THAT FL320 WAS 'A GOOD RIDE;' OR IF THEY DIDN'T HAVE ANY ACTIVE 'BAD' TURB RIDE RPTS; BUT THE HIGHER ALTS SEEMED WORSE IN ANY CASE. WE PLANNED (ON THE GND) FOR AND REQUESTED (IN THE AIR) FL320. DURING CLB; WE DID NOT HIT THE FORECAST/RPTED MODERATE TURB; ENCOUNTERING ONLY LIGHT TURB IN A COUPLE OF SPOTS; AND LIGHT CHOP TO SMOOTH ELSEWHERE. EVEN THOUGH IT WAS FAIRLY SMOOTH DURING THE UPPER CLB; I KEPT THE SEATBELT SIGN ON UNTIL AFTER REACHING CRUISE. TURB INCIDENT: NEAR ABEAM MLI/MZV; WE ENCOUNTERED A MOMENTARY MODERATE TURB; OR JOLT. IT SEEMED LIKE JUST ONE. VERY SHORT DURATION. I DON'T RECALL ANY NEGATIVE FORCES; JUST A VERY POSITIVE JOLT. NOTHING TO MY KNOWLEDGE MOVED IN THE COCKPIT; EVEN OPEN DRINKS IN THE COCKPIT DID NOT SPILL. SHORTLY AFTER; THE PURSER CALLED TO INFORM US OF MULTIPLE INJURIES; THE WORST OF WHICH SEEMED TO BE A PAX HEAD GASH; WITH 'LOTS' OF BLOOD. THE CABIN AT THIS POINT STARTED ADDRESSING THE INJURIES WITH RECRUITMENT OF A MEDICAL DOCTOR PAX; ACCESSING FIRST AID KITS; AND CABIN CLEAN-UP. WE INFORMED ATC OF THE ENCOUNTER AND STARTED THE PROCESS OF A DIVERSION THROUGH ATC AND DISPATCH. IT SEEMED TO TAKE A LONG TIME TO START GETTING ACCURATE INFO FROM THE CABIN; AS WELL AS COORDINATING WITH DISPATCH. IN ACTUALITY; IT PROBABLY WENT PRETTY QUICKLY AND EFFICIENTLY. WE HAD AN OFFLINE JUMPSEATER; WHO WE SENT TO THE CABIN TO START GATHERING DETAILED INFO ON INJURIES. HE WAS A GREAT RESOURCE AND HELPED A LOT. I SUPPOSE IT SEEMED LIKE A LONG TIME BECAUSE I STILL DIDN'T HAVE ANY INFO WHETHER OR NOT ANY INJURIES WERE LIFE THREATENING AND WHAT OUR DIVERT DECISION NEEDED TO BE. WE FINALLY DID START TO GET INFO THAT NONE OF THE INJURIES WERE LIFE THREATENING. I HAD IT CONFIRMED A SECOND TIME AS WELL. WE COORDINATED WITH DISPATCH AND DECISION TO CONTINUE TO LAX WAS MADE; CONSIDERING ARPTS ALONG RTE FOR POSSIBLE DIVERSION IF STATUS OF INJURIES DETERIORATED. FURTHER INFO FROM CABIN SHOWED 3 PAX INJURIES -- THE HEAD LACERATION; AND OTHER BUMPS AND BRUISES; AND 3 FLT ATTENDANTS INJURED KNEES AND ANKLE. ALL BUT 1 FLT ATTENDANT CONTINUED WORKING; AS WELL AS ONE FLT ATTENDANT JUMPSEATER ALSO VOLUNTEERED TO WORK. WE DISCUSSED THE INTENSITY OF THE ENCOUNTER AND DECIDED THAT IT WAS MODERATE. WE CONSIDERED A SEVERE DECLARATION; BUT THERE WAS NO AIRPLANE LOSS OF CTL; NOR ANY OBSERVED ALT OR ATTITUDE DEVS; NO MOVING OBJECTS OR SPILLED DRINKS IN THE COCKPIT. THE CABIN DID EXPERIENCE SOME PAX AND FLT ATTENDANTS FALLING DOWN; AND SOME GALLEY ITEMS FALLING. SINCE THE CONDITIONS WERE FAVORABLE JUST PRIOR TO THE EVENT; A LACK OF PREPAREDNESS MAY HAVE BEEN THE REASON FOR THE MULTIPLE INJURIES. ALSO; CONSIDERING THE INTENSITY CALL; ATC DID QUERY US A NUMBER OF TIMES IF IT WAS SEVERE; OR ABOUT THE TURB SEVERITY. I DO NOT THINK I TERMED IT SEVERE; BUT IN THE HEAT OF THE MOMENT; I DO NOT KNOW. AFTERWARD; WE ATTEMPTED TO CLARIFY IT AS MODERATE.

Data retrieved from NASA's ASRS site as of January 2009 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.