Narrative:

While deviating to avoid thunderstorms we observed on radar an opening between cells of approximately 45 mi. The opening would allow us back on ATC route and south of a line of scattered thunderstorms ahead and parallel to our route. The ride was smooth, occasional light chop. When through the opening and WX radar showed us 20 NM southeast of the closest cell to our right, we momentarily were VMC and saw a cumulo nimbus directly ahead and too close to avoid. A PA announcement was made for the flight attendants to situation, but there wasn't time. We flew through the top of the cumulo nimbus, encountered 10 seconds of severe turbulence, approximately 900 ft altitude loss, airspeed from .80 mach to .74 mach. 2 flight attendants and 1 passenger were reported injured and we diverted to stl. The seat belt sign was on for the entire duration and detour. The WX radar was giving an apparently good presentation using different ranges and tilt settings. The visibility was restr by high cirus/haze. In stl the injured were taken to the hospital. The aircraft was inspected per required procedures. Airplane and passenger departed for sfo at XA40Z. Callback conversation with reporter revealed the following: the flight crew was circumnaving an area of isolated thunderstorms in their B767-200 and everything looked clear on their proposed route. However, as they were turning toward their next point they encountered some cirrus clouds that restr their forward visibility. The captain looked down at the radar and then adjusted its tilt control to attempt to determine if there were any WX of interest ahead of them. He looked up upon the first officer's exclamation and saw a column of cloud too close to avoid. This cloud did not show on radar. The captain quickly made a PA to have the flight attendants situation down and they hit the cloud. The aircraft did not change pitch, but instead settled very rapidly. The first officer, who was flying took the aircraft off the autoplt and autothrottles and allowed the aircraft to continue its downward movement without any great attempt to apply back pressure as they did not want to cause a stall or other secondary event. The ride in the rear of the aircraft was, in the captain's words, 'worse than in the front because that's where the injuries were. The forward flight attendants were held by passenger and they were not injured.' the captain said further that he already had the seat belt sign on and he put the ignition switch on after he made the warning PA. The upset started with a sharp jolt then they settled. 1 flight attendant had 2 different fractures of the pelvis, another had 1 fracture of the pelvis and a broken wrist, another flight attendant had a sprained ankle that later was put in a cast and there was a passenger, who was not wearing her seat belt, who was injured.

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Original NASA ASRS Text

Title: WX FACTORS - ACR ENCOUNTERS SEVERE TURB LOSES 900 FT AND HAS INJURIES TO A PAX AND SEVERAL FLT ATTENDANTS.

Narrative: WHILE DEVIATING TO AVOID TSTMS WE OBSERVED ON RADAR AN OPENING BTWN CELLS OF APPROX 45 MI. THE OPENING WOULD ALLOW US BACK ON ATC RTE AND S OF A LINE OF SCATTERED TSTMS AHEAD AND PARALLEL TO OUR RTE. THE RIDE WAS SMOOTH, OCCASIONAL LIGHT CHOP. WHEN THROUGH THE OPENING AND WX RADAR SHOWED US 20 NM SE OF THE CLOSEST CELL TO OUR R, WE MOMENTARILY WERE VMC AND SAW A CUMULO NIMBUS DIRECTLY AHEAD AND TOO CLOSE TO AVOID. A PA ANNOUNCEMENT WAS MADE FOR THE FLT ATTENDANTS TO SIT, BUT THERE WASN'T TIME. WE FLEW THROUGH THE TOP OF THE CUMULO NIMBUS, ENCOUNTERED 10 SECONDS OF SEVERE TURB, APPROX 900 FT ALT LOSS, AIRSPD FROM .80 MACH TO .74 MACH. 2 FLT ATTENDANTS AND 1 PAX WERE RPTED INJURED AND WE DIVERTED TO STL. THE SEAT BELT SIGN WAS ON FOR THE ENTIRE DURATION AND DETOUR. THE WX RADAR WAS GIVING AN APPARENTLY GOOD PRESENTATION USING DIFFERENT RANGES AND TILT SETTINGS. THE VISIBILITY WAS RESTR BY HIGH CIRUS/HAZE. IN STL THE INJURED WERE TAKEN TO THE HOSPITAL. THE ACFT WAS INSPECTED PER REQUIRED PROCS. AIRPLANE AND PAX DEPARTED FOR SFO AT XA40Z. CALLBACK CONVERSATION WITH REPORTER REVEALED THE FOLLOWING: THE FLC WAS CIRCUMNAVING AN AREA OF ISOLATED TSTMS IN THEIR B767-200 AND EVERYTHING LOOKED CLR ON THEIR PROPOSED RTE. HOWEVER, AS THEY WERE TURNING TOWARD THEIR NEXT POINT THEY ENCOUNTERED SOME CIRRUS CLOUDS THAT RESTR THEIR FORWARD VISIBILITY. THE CAPT LOOKED DOWN AT THE RADAR AND THEN ADJUSTED ITS TILT CTL TO ATTEMPT TO DETERMINE IF THERE WERE ANY WX OF INTEREST AHEAD OF THEM. HE LOOKED UP UPON THE FO'S EXCLAMATION AND SAW A COLUMN OF CLOUD TOO CLOSE TO AVOID. THIS CLOUD DID NOT SHOW ON RADAR. THE CAPT QUICKLY MADE A PA TO HAVE THE FLT ATTENDANTS SIT DOWN AND THEY HIT THE CLOUD. THE ACFT DID NOT CHANGE PITCH, BUT INSTEAD SETTLED VERY RAPIDLY. THE FO, WHO WAS FLYING TOOK THE ACFT OFF THE AUTOPLT AND AUTOTHROTTLES AND ALLOWED THE ACFT TO CONTINUE ITS DOWNWARD MOVEMENT WITHOUT ANY GREAT ATTEMPT TO APPLY BACK PRESSURE AS THEY DID NOT WANT TO CAUSE A STALL OR OTHER SECONDARY EVENT. THE RIDE IN THE REAR OF THE ACFT WAS, IN THE CAPT'S WORDS, 'WORSE THAN IN THE FRONT BECAUSE THAT'S WHERE THE INJURIES WERE. THE FORWARD FLT ATTENDANTS WERE HELD BY PAX AND THEY WERE NOT INJURED.' THE CAPT SAID FURTHER THAT HE ALREADY HAD THE SEAT BELT SIGN ON AND HE PUT THE IGNITION SWITCH ON AFTER HE MADE THE WARNING PA. THE UPSET STARTED WITH A SHARP JOLT THEN THEY SETTLED. 1 FLT ATTENDANT HAD 2 DIFFERENT FRACTURES OF THE PELVIS, ANOTHER HAD 1 FRACTURE OF THE PELVIS AND A BROKEN WRIST, ANOTHER FLT ATTENDANT HAD A SPRAINED ANKLE THAT LATER WAS PUT IN A CAST AND THERE WAS A PAX, WHO WAS NOT WEARING HER SEAT BELT, WHO WAS INJURED.

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.