Narrative:

Position estimated 30 mi west of waypoint erwen (223006N 151.33.54W ZHN) on R577 FL370, first officer acting as PF. Approximately 25 mins after takeoff, 5 mins into cruise flight, aircraft experienced moderate to severe turbulence lasting approximately 10-15 seconds. Flight conditions, on top of clouds, in clear air, radar on, autoplt on, seat belt sign off, no reports of turbulence nor choppy air encountered during climb, smooth cruise flight. Initially aircraft encountered sudden moderate turbulence lasting approximately 4 seconds, seat belt sign turned to on. As PA was being performed aircraft shaken violently. Abrupt changes in altitude estimated -300 to +400 ft. Erratic attitude changes and noted loss of approximately 30 KIAS. First officer noted estimated 20 KT increase in displayed tailwind on HSI. Severe turbulence lasted approximately 10 seconds followed by moderate chop conditions for short period thereafter. During entire encounter autoplt remained on, no aircraft limitations were exceeded. Immediately checked with both purser and aft flight attendant position via interphone to assess any passenger or crew injuries. Further PA performed to calm passenger. No injuries reported, some passenger reported visibly shaken, a few crying. Able to report severe turbulence to ZHN on 126.6 and receive acknowledgement. Aircraft handling characteristics remained consistent, no discrepancies noted. Flight continued on to lax. Prior to landing air carrier maintenance was notified via radio of severe turbulence encounter for heads up on inspection requirement. After landing, dispatch debriefed via telephone. Approximately 45 mins after turbulence encounter, informed by purser that #5 flight attendant complaining of back pain. I spoke directly to #5 flight attendant via interphone and was informed that she could continue to perform her flight attendant duties. Flight attendant #5 came to the cockpit at approximately 2 hours 20 mins into the flight to get additional information for her reporting purposes. Learned only at that time that #4 flight attendant was also complaining of back pain. In passing conversation, flight attendant #5 noted that passenger in seat xb had complained of back hurting. Asked for passenger name and information and coordinated efforts through purser. Passenger was found sleeping, would relay information later. Name of possibly injured passenger can be found in purser's report, apparently information given to her after landing. Personally assisted in deplaning all passenger. Comments of a wild ride, can we do that again, many thank yous and shaking of my hand, no passenger complaints of any injury during deplaning. Supplemental information from acn 590462: unfortunately, with clear air turbulence, there is not really anything you can do to prevent what occurred. It happened quite suddenly, the normal turbulence we sometimes experience and then a quick drop followed by us all being thrown about quite violently. I was lucky enough to be 'saved' by a passenger in the 'X' seat who literally held me down for roughly about 6-10 mins. We were all visibly shaken -- it really came out of nowhere. As we tried to reach our jumpseats, passenger are trying to stop us to ask questions. We are desperately trying to situation down and some passenger are trying to stop us to get answers. Even with the pilot apologizing for the turbulence and requesting the flight attendants to situation, they're trying to stop us. Many passenger were crying, one so loud she was upsetting the other passenger. Perhaps we could do something about the #1 flight attendant seated to make an announcement that the flight attendants need to take their seats immediately and the captain would explain the situation when he could (which he did). When we resumed our service, I heard a passenger say to another, 'did you see that lightning?' we were not told that there was even a thunderstorm going on.

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Original NASA ASRS Text

Title: SOME FLT ATTENDANTS AND PAX INJURIES RPTED DURING A SEVERE TURB ENCOUNTER BY A B757 FLT CREW E OF HAWAII, R-577, FL370, ON FREQ WITH ZHN, HI.

Narrative: POS ESTIMATED 30 MI W OF WAYPOINT ERWEN (223006N 151.33.54W ZHN) ON R577 FL370, FO ACTING AS PF. APPROX 25 MINS AFTER TKOF, 5 MINS INTO CRUISE FLT, ACFT EXPERIENCED MODERATE TO SEVERE TURB LASTING APPROX 10-15 SECONDS. FLT CONDITIONS, ON TOP OF CLOUDS, IN CLR AIR, RADAR ON, AUTOPLT ON, SEAT BELT SIGN OFF, NO RPTS OF TURB NOR CHOPPY AIR ENCOUNTERED DURING CLB, SMOOTH CRUISE FLT. INITIALLY ACFT ENCOUNTERED SUDDEN MODERATE TURB LASTING APPROX 4 SECONDS, SEAT BELT SIGN TURNED TO ON. AS PA WAS BEING PERFORMED ACFT SHAKEN VIOLENTLY. ABRUPT CHANGES IN ALT ESTIMATED -300 TO +400 FT. ERRATIC ATTITUDE CHANGES AND NOTED LOSS OF APPROX 30 KIAS. FO NOTED ESTIMATED 20 KT INCREASE IN DISPLAYED TAILWIND ON HSI. SEVERE TURB LASTED APPROX 10 SECONDS FOLLOWED BY MODERATE CHOP CONDITIONS FOR SHORT PERIOD THEREAFTER. DURING ENTIRE ENCOUNTER AUTOPLT REMAINED ON, NO ACFT LIMITATIONS WERE EXCEEDED. IMMEDIATELY CHKED WITH BOTH PURSER AND AFT FLT ATTENDANT POS VIA INTERPHONE TO ASSESS ANY PAX OR CREW INJURIES. FURTHER PA PERFORMED TO CALM PAX. NO INJURIES RPTED, SOME PAX RPTED VISIBLY SHAKEN, A FEW CRYING. ABLE TO RPT SEVERE TURB TO ZHN ON 126.6 AND RECEIVE ACKNOWLEDGEMENT. ACFT HANDLING CHARACTERISTICS REMAINED CONSISTENT, NO DISCREPANCIES NOTED. FLT CONTINUED ON TO LAX. PRIOR TO LNDG ACR MAINT WAS NOTIFIED VIA RADIO OF SEVERE TURB ENCOUNTER FOR HEADS UP ON INSPECTION REQUIREMENT. AFTER LNDG, DISPATCH DEBRIEFED VIA TELEPHONE. APPROX 45 MINS AFTER TURB ENCOUNTER, INFORMED BY PURSER THAT #5 FLT ATTENDANT COMPLAINING OF BACK PAIN. I SPOKE DIRECTLY TO #5 FLT ATTENDANT VIA INTERPHONE AND WAS INFORMED THAT SHE COULD CONTINUE TO PERFORM HER FLT ATTENDANT DUTIES. FLT ATTENDANT #5 CAME TO THE COCKPIT AT APPROX 2 HRS 20 MINS INTO THE FLT TO GET ADDITIONAL INFO FOR HER RPTING PURPOSES. LEARNED ONLY AT THAT TIME THAT #4 FLT ATTENDANT WAS ALSO COMPLAINING OF BACK PAIN. IN PASSING CONVERSATION, FLT ATTENDANT #5 NOTED THAT PAX IN SEAT XB HAD COMPLAINED OF BACK HURTING. ASKED FOR PAX NAME AND INFO AND COORDINATED EFFORTS THROUGH PURSER. PAX WAS FOUND SLEEPING, WOULD RELAY INFO LATER. NAME OF POSSIBLY INJURED PAX CAN BE FOUND IN PURSER'S RPT, APPARENTLY INFO GIVEN TO HER AFTER LNDG. PERSONALLY ASSISTED IN DEPLANING ALL PAX. COMMENTS OF A WILD RIDE, CAN WE DO THAT AGAIN, MANY THANK YOUS AND SHAKING OF MY HAND, NO PAX COMPLAINTS OF ANY INJURY DURING DEPLANING. SUPPLEMENTAL INFO FROM ACN 590462: UNFORTUNATELY, WITH CLR AIR TURB, THERE IS NOT REALLY ANYTHING YOU CAN DO TO PREVENT WHAT OCCURRED. IT HAPPENED QUITE SUDDENLY, THE NORMAL TURB WE SOMETIMES EXPERIENCE AND THEN A QUICK DROP FOLLOWED BY US ALL BEING THROWN ABOUT QUITE VIOLENTLY. I WAS LUCKY ENOUGH TO BE 'SAVED' BY A PAX IN THE 'X' SEAT WHO LITERALLY HELD ME DOWN FOR ROUGHLY ABOUT 6-10 MINS. WE WERE ALL VISIBLY SHAKEN -- IT REALLY CAME OUT OF NOWHERE. AS WE TRIED TO REACH OUR JUMPSEATS, PAX ARE TRYING TO STOP US TO ASK QUESTIONS. WE ARE DESPERATELY TRYING TO SIT DOWN AND SOME PAX ARE TRYING TO STOP US TO GET ANSWERS. EVEN WITH THE PLT APOLOGIZING FOR THE TURB AND REQUESTING THE FLT ATTENDANTS TO SIT, THEY'RE TRYING TO STOP US. MANY PAX WERE CRYING, ONE SO LOUD SHE WAS UPSETTING THE OTHER PAX. PERHAPS WE COULD DO SOMETHING ABOUT THE #1 FLT ATTENDANT SEATED TO MAKE AN ANNOUNCEMENT THAT THE FLT ATTENDANTS NEED TO TAKE THEIR SEATS IMMEDIATELY AND THE CAPT WOULD EXPLAIN THE SIT WHEN HE COULD (WHICH HE DID). WHEN WE RESUMED OUR SVC, I HEARD A PAX SAY TO ANOTHER, 'DID YOU SEE THAT LIGHTNING?' WE WERE NOT TOLD THAT THERE WAS EVEN A TSTM GOING ON.

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.