Narrative:

Prior to take off [on our transoceanic flight] we received a message from the dispatcher that a 747 had encountered severe turbulence over the calma fix at FL290. The dispatcher suggested that we stay below FL270 until past the calma fix. The first officer requested an initial altitude of FL250 with a back up of FL270 with clearance delivery. Clearance delivery assigned us FL270.prior to flight I briefed the purser that there would be turbulence. From the weather depiction it looked as if the turbulence would occur between 180E and 170W. This was approximately 3:30 into the flight. So I mentioned that she should plan her service accordingly. Once I found out about the turbulence report; I asked her to come up to the cockpit and I briefed her a second time with regard to the current report. I mentioned that the report was over a fix that was approximately 30-40 minutes after takeoff. I reiterated that this type of turbulence report was the type that could hurt her crew if they were not seated. She understood and acknowledged and mentioned that she would brief the crew and asked if I would make an announcement. I mentioned that I would make a PA telling the flight attendants to be seated when I received good and updated information.the flight proceeded normally. Approximately 15 minutes out of calma I started hearing reports on frequency that there was rough air over calma. I also received several notifications from the dispatcher prior to that point regarding the turbulence reports. Approximately 15 prior to calma I turned on the seat belt sign and made the appropriate announcement over the PA. Approximately 10 minutes prior to calma I made a second PA instructing the flight attendants to take their seats. Approximately 5 minutes out of calma until about 5 minutes past calma we encounter heavy moderate and occasional severe turbulence due to wave action. I slowed the aircraft to ensure that we were at turbulence penetration speed and maneuvered to ensure that we did not enter the cumulus and lenticular clouds that were present in the area. The aircraft lost and gained approximately 100 feet and airspeed varied from plus or minus 25 knots.upon exiting the area of turbulence; we made a PIREP and reported to the dispatcher the ride report and our status. The aircraft was operating normally and we continued the flight. I also called the purser and inquired if everyone was ok. She mentioned that people were shaken but everything was ok. Later; I found out that two of the flight attendants had sustained minor injuries. One had bumped her head on a galley door and another injured her knee on a service cart. Throughout the flight I inquired personally of both of the injured flight attendants as to how they were doing with their injuries. Both indicated that they were fine to continue their duties.

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Original NASA ASRS Text

Title: A heavy jet on a transoceanic flight encountered moderate to severe turbulence resulting in minor injuries to several Flight Attendants.

Narrative: Prior to take off [on our transoceanic flight] we received a message from the Dispatcher that a 747 had encountered severe turbulence over the CALMA fix at FL290. The Dispatcher suggested that we stay below FL270 until past the CALMA fix. The First Officer requested an initial altitude of FL250 with a back up of FL270 with clearance delivery. Clearance delivery assigned us FL270.Prior to flight I briefed the Purser that there would be turbulence. From the weather depiction it looked as if the turbulence would occur between 180E and 170W. This was approximately 3:30 into the flight. So I mentioned that she should plan her service accordingly. Once I found out about the turbulence report; I asked her to come up to the cockpit and I briefed her a second time with regard to the current report. I mentioned that the report was over a fix that was approximately 30-40 minutes after takeoff. I reiterated that this type of turbulence report was the type that could hurt her crew if they were not seated. She understood and acknowledged and mentioned that she would brief the crew and asked if I would make an announcement. I mentioned that I would make a PA telling the Flight Attendants to be seated when I received good and updated information.The flight proceeded normally. Approximately 15 minutes out of CALMA I started hearing reports on frequency that there was rough air over CALMA. I also received several notifications from the dispatcher prior to that point regarding the turbulence reports. Approximately 15 prior to CALMA I turned on the seat belt sign and made the appropriate announcement over the PA. Approximately 10 minutes prior to CALMA I made a second PA instructing the flight attendants to take their seats. Approximately 5 minutes out of CALMA until about 5 minutes past CALMA we encounter heavy moderate and occasional severe turbulence due to wave action. I slowed the aircraft to ensure that we were at turbulence penetration speed and maneuvered to ensure that we did not enter the cumulus and lenticular clouds that were present in the area. The aircraft lost and gained approximately 100 feet and airspeed varied from plus or minus 25 knots.Upon exiting the area of turbulence; we made a PIREP and reported to the Dispatcher the ride report and our status. The aircraft was operating normally and we continued the flight. I also called the Purser and inquired if everyone was OK. She mentioned that people were shaken but everything was OK. Later; I found out that two of the flight attendants had sustained minor injuries. One had bumped her head on a galley door and another injured her knee on a service cart. Throughout the flight I inquired personally of both of the injured flight attendants as to how they were doing with their injuries. Both indicated that they were fine to continue their duties.

Data retrieved from NASA's ASRS site as of April 2012 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.