Narrative:

While deviating around thunderstorms at FL350, it had been a very smooth ride and so the captain (who told flight attendants earlier to be seated) told them they could resume service, with the seat belt sign turned on. Just a short time after he did this we hit 5-8 seconds worth of moderate turbulence due to the WX we had been deviating around. Carts were jarred and 3 flight attendants reported stiffness and 1 of these 3 reported that she hit her head. I constantly wonder why it is ok for flight attendants to be walking around when we have the seat belt sign on for passenger. If I were captain I would be much more conservative when dealing with turbulence and if in doubt keep everyone seated.

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Original NASA ASRS Text

Title: 3 CABIN ATTENDANTS INJURED WHEN B767 ENCOUNTERS MODERATE TURB IN VICINITY OF CONVECTIVE WX. RPTR FAULTS CAPT FOR ALLOWING ATTENDANTS TO CONTINUE SVC WHILE SEAT BELT SIGN STILL ON FOR PAX.

Narrative: WHILE DEVIATING AROUND TSTMS AT FL350, IT HAD BEEN A VERY SMOOTH RIDE AND SO THE CAPT (WHO TOLD FLT ATTENDANTS EARLIER TO BE SEATED) TOLD THEM THEY COULD RESUME SVC, WITH THE SEAT BELT SIGN TURNED ON. JUST A SHORT TIME AFTER HE DID THIS WE HIT 5-8 SECONDS WORTH OF MODERATE TURB DUE TO THE WX WE HAD BEEN DEVIATING AROUND. CARTS WERE JARRED AND 3 FLT ATTENDANTS RPTED STIFFNESS AND 1 OF THESE 3 RPTED THAT SHE HIT HER HEAD. I CONSTANTLY WONDER WHY IT IS OK FOR FLT ATTENDANTS TO BE WALKING AROUND WHEN WE HAVE THE SEAT BELT SIGN ON FOR PAX. IF I WERE CAPT I WOULD BE MUCH MORE CONSERVATIVE WHEN DEALING WITH TURB AND IF IN DOUBT KEEP EVERYONE SEATED.

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.