Narrative:

At 31000 ft, between cmh and day, we experienced light turbulence, in clear VFR, no cloud formations or temperature wind or atmospheric condition present to indicate turbulence would increase. I put seat belt sign 'on,' asked ATC about rides. Only light turbulence was reported in area, but 28000 ft was a better ride. I requested 28000 ft and started a slow 1000 FPM descent (mach .74 normal speed). We then hit 1 severe chop. No structural limits were exceeded. Checked with flight attendants, 2 were seated. Our 3RD flight attendant was on way to rear flight station. She fell and was injured. (Broken foot, found out next day) orthopedic doctor on board helped. We did not declare medical emergency. All company checklist and procedures were followed and completed to a normal landing.

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Original NASA ASRS Text

Title: ACR MLG ENCOUNTERS CLR AIR TURB IN CRUISE, CABIN ATTENDANT INJURED.

Narrative: AT 31000 FT, BTWN CMH AND DAY, WE EXPERIENCED LIGHT TURB, IN CLR VFR, NO CLOUD FORMATIONS OR TEMP WIND OR ATMOSPHERIC CONDITION PRESENT TO INDICATE TURB WOULD INCREASE. I PUT SEAT BELT SIGN 'ON,' ASKED ATC ABOUT RIDES. ONLY LIGHT TURB WAS RPTED IN AREA, BUT 28000 FT WAS A BETTER RIDE. I REQUESTED 28000 FT AND STARTED A SLOW 1000 FPM DSCNT (MACH .74 NORMAL SPD). WE THEN HIT 1 SEVERE CHOP. NO STRUCTURAL LIMITS WERE EXCEEDED. CHKED WITH FLT ATTENDANTS, 2 WERE SEATED. OUR 3RD FLT ATTENDANT WAS ON WAY TO REAR FLT STATION. SHE FELL AND WAS INJURED. (BROKEN FOOT, FOUND OUT NEXT DAY) ORTHOPEDIC DOCTOR ON BOARD HELPED. WE DID NOT DECLARE MEDICAL EMER. ALL COMPANY CHKLIST AND PROCS WERE FOLLOWED AND COMPLETED TO A NORMAL LNDG.

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.