Narrative:

In foreign airspace at FL340 diverting in clear air on the upwind side of some build ups we encountered moderate turbulence. The seat belt sign was on but two flight attendants were in the very back of the aircraft working in the aisle with the cart. It looked as though we would clear the tops of the buildups but at the last minute we just went through the tops. There was one moderate bump of turbulence. I called back to the flight attendants and they informed me that they had both hit the ceiling and the cart had turned over. I asked if they were hurt and they said yes. Further discovery revealed they both required medical help. I turned the flying duties over to my first officer and asked him to declare an emergency and we diverted to a nearby foreign airport. I got a phone patch through commercial radio with dispatch and told them we were diverting with a medical emergency with two flight attendants injured and requested medical help upon arrival. We landed uneventfully. My first officer and the number 1 and 3 flight attendants performed their duties perfectly. The station personnel did a superb job of making arrangements for our passengers. In retrospect I should have given more clearance to this build up even though we appeared to be well above it and on the back side of it. I was trained that you should use the HUD to determine your flight path vector above or around build ups. This training has worked perfectly until now. It clearly did not work in this case. I will never use the HUD guidance for avoiding build ups again.

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Original NASA ASRS Text

Title: A B737 passed in the top of a thunderstorm where moderate turbulence injured two flight attendants and turned over the beverage cart so an emergency was declared and the flight diverted to a nearby foreign airport for medical attention.

Narrative: In Foreign Airspace at FL340 diverting in clear air on the upwind side of some build ups we encountered moderate turbulence. The seat belt sign was on but two flight attendants were in the very back of the aircraft working in the aisle with the cart. It looked as though we would clear the tops of the buildups but at the last minute we just went through the tops. There was one moderate bump of turbulence. I called back to the flight attendants and they informed me that they had both hit the ceiling and the cart had turned over. I asked if they were hurt and they said yes. Further discovery revealed they both required medical help. I turned the flying duties over to my First Officer and asked him to declare an emergency and we diverted to a nearby foreign airport. I got a phone patch through Commercial Radio with Dispatch and told them we were diverting with a Medical Emergency with two flight attendants injured and requested medical help upon arrival. We landed uneventfully. My First Officer and the number 1 and 3 Flight Attendants performed their duties perfectly. The station personnel did a superb job of making arrangements for our passengers. In retrospect I should have given more clearance to this build up even though we appeared to be well above it and on the back side of it. I was trained that you should use the HUD to determine your Flight Path Vector above or around build ups. This training has worked perfectly until now. It clearly did not work in this case. I will never use the HUD guidance for avoiding build ups again.

Data retrieved from NASA's ASRS site as of July 2013 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.