Narrative:

Conducted flight xy per air carrier training and operational procedures on assigned flight plan from mia to ams. At FL350, approaching 32 degrees west longitude, we began to encounter turbulence. Pilots initiated calls for ATC clearance to lower altitude to improve the ride. Company training and procedures utilized to notify and prepare cabin crew and passenger for encountered turbulence. Approaching 30 degrees west, began ATC-authority/authorized descent from FL350 to FL340. At this point turbulence increased significantly. The autoplt disconnected (uncommanded) and autothrottles disengaged. First officer hand flew aircraft in descent until turbulence decreased (approximately FL345). Upon leveloff at FL340, I noted no aircraft system degradation and that autoplt and autothrottles re-engaged. Purser reported possible injury to flight attendant at door 4L. ATC and dispatch notified as to situation. Arranged for emergency medical to meet flight at ams gate. Uneventful descent and landing at ams. 1 flight attendant transported to local hospital. Cause: probable clear air turbulence that was unobserved and unpredicted.

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Original NASA ASRS Text

Title: DC10 IS CAUGHT IN CLR AIR TURB DURING OCEANIC FLT CAUSING INJURY TO 1 CABIN ATTENDANT. MEDICAL EMER WAS DECLARED AND MEDICS MET ACFT AT GATE ON ARR.

Narrative: CONDUCTED FLT XY PER ACR TRAINING AND OPERATIONAL PROCS ON ASSIGNED FLT PLAN FROM MIA TO AMS. AT FL350, APCHING 32 DEGS W LONGITUDE, WE BEGAN TO ENCOUNTER TURB. PLTS INITIATED CALLS FOR ATC CLRNC TO LOWER ALT TO IMPROVE THE RIDE. COMPANY TRAINING AND PROCS UTILIZED TO NOTIFY AND PREPARE CABIN CREW AND PAX FOR ENCOUNTERED TURB. APCHING 30 DEGS W, BEGAN ATC-AUTH DSCNT FROM FL350 TO FL340. AT THIS POINT TURB INCREASED SIGNIFICANTLY. THE AUTOPLT DISCONNECTED (UNCOMMANDED) AND AUTOTHROTTLES DISENGAGED. FO HAND FLEW ACFT IN DSCNT UNTIL TURB DECREASED (APPROX FL345). UPON LEVELOFF AT FL340, I NOTED NO ACFT SYS DEGRADATION AND THAT AUTOPLT AND AUTOTHROTTLES RE-ENGAGED. PURSER RPTED POSSIBLE INJURY TO FLT ATTENDANT AT DOOR 4L. ATC AND DISPATCH NOTIFIED AS TO SIT. ARRANGED FOR EMER MEDICAL TO MEET FLT AT AMS GATE. UNEVENTFUL DSCNT AND LNDG AT AMS. 1 FLT ATTENDANT TRANSPORTED TO LCL HOSPITAL. CAUSE: PROBABLE CLR AIR TURB THAT WAS UNOBSERVED AND UNPREDICTED.

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.