Narrative:

We were confronted by a line of thunderstorms during our climb, north of cincinnati. Our radar showed a break in the line, containing only 2 small cells, 1 contouring slightly, and the other consisting of only rain, separated by clear area of about 18 mi or so. Although it did look like a potentially acceptable transit area, we asked ATC for a deviation around the east end of the WX, so as to avoid it altogether. Following our request for deviation, the controller replied that there was a significant break at our 11 O'clock, (the one we had observed), that other aircraft were using, that would take us over fort wayne and allow us to join the mizar arrival into detroit from that direction. We advised the lead flight attendant of the possibility of some turbulence for the next 10 mins or so, and proceeded to transit the break in the line. We stayed in the area of no radar return between the 2 cells, slightly favoring the cell that was not contouring. Although it appeared to be a 'young' cell with only rain, it must have been building very rapidly, because as we went past it, we experienced a short burst of severe turbulence, perhaps 5-10 seconds in duration, that spilled drinks everywhere in the cabin, and caused a flight attendant who was in the lavatory, to hit her head rather hard on the ceiling. Although the ultimate cause of this incident was faulty judgement on my part, and I accept full responsibility for it, I feel that we were led away from our initial decision (to avoid the WX altogether), by a well intentioned controller. I have never depended on the controllers to keep me clear of the WX. (I used to be one, and I know that their radar is designed to paint airplanes, not thunderstorms.) they have, however, often provided me with valuable information regarding the WX, which assisted me in making my own decision as to the best route for safe transit of a storm-infested area. I feel that both pilots and controllers need to be more aware of the limitations of our own on-board radar in predicting turbulence. Just because you don't see anything on the scope doesn't mean there's not something there that can give you a wild ride and maybe hurt someone.

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Original NASA ASRS Text

Title: AN ACR MLG GOT INTO SOME SEVERE TURB. A FLT ATTENDANT WAS INJURED.

Narrative: WE WERE CONFRONTED BY A LINE OF TSTMS DURING OUR CLB, N OF CINCINNATI. OUR RADAR SHOWED A BREAK IN THE LINE, CONTAINING ONLY 2 SMALL CELLS, 1 CONTOURING SLIGHTLY, AND THE OTHER CONSISTING OF ONLY RAIN, SEPARATED BY CLR AREA OF ABOUT 18 MI OR SO. ALTHOUGH IT DID LOOK LIKE A POTENTIALLY ACCEPTABLE TRANSIT AREA, WE ASKED ATC FOR A DEV AROUND THE E END OF THE WX, SO AS TO AVOID IT ALTOGETHER. FOLLOWING OUR REQUEST FOR DEV, THE CTLR REPLIED THAT THERE WAS A SIGNIFICANT BREAK AT OUR 11 O'CLOCK, (THE ONE WE HAD OBSERVED), THAT OTHER ACFT WERE USING, THAT WOULD TAKE US OVER FORT WAYNE AND ALLOW US TO JOIN THE MIZAR ARR INTO DETROIT FROM THAT DIRECTION. WE ADVISED THE LEAD FLT ATTENDANT OF THE POSSIBILITY OF SOME TURB FOR THE NEXT 10 MINS OR SO, AND PROCEEDED TO TRANSIT THE BREAK IN THE LINE. WE STAYED IN THE AREA OF NO RADAR RETURN BTWN THE 2 CELLS, SLIGHTLY FAVORING THE CELL THAT WAS NOT CONTOURING. ALTHOUGH IT APPEARED TO BE A 'YOUNG' CELL WITH ONLY RAIN, IT MUST HAVE BEEN BUILDING VERY RAPIDLY, BECAUSE AS WE WENT PAST IT, WE EXPERIENCED A SHORT BURST OF SEVERE TURB, PERHAPS 5-10 SECONDS IN DURATION, THAT SPILLED DRINKS EVERYWHERE IN THE CABIN, AND CAUSED A FLT ATTENDANT WHO WAS IN THE LAVATORY, TO HIT HER HEAD RATHER HARD ON THE CEILING. ALTHOUGH THE ULTIMATE CAUSE OF THIS INCIDENT WAS FAULTY JUDGEMENT ON MY PART, AND I ACCEPT FULL RESPONSIBILITY FOR IT, I FEEL THAT WE WERE LED AWAY FROM OUR INITIAL DECISION (TO AVOID THE WX ALTOGETHER), BY A WELL INTENTIONED CTLR. I HAVE NEVER DEPENDED ON THE CTLRS TO KEEP ME CLR OF THE WX. (I USED TO BE ONE, AND I KNOW THAT THEIR RADAR IS DESIGNED TO PAINT AIRPLANES, NOT TSTMS.) THEY HAVE, HOWEVER, OFTEN PROVIDED ME WITH VALUABLE INFO REGARDING THE WX, WHICH ASSISTED ME IN MAKING MY OWN DECISION AS TO THE BEST RTE FOR SAFE TRANSIT OF A STORM-INFESTED AREA. I FEEL THAT BOTH PLTS AND CTLRS NEED TO BE MORE AWARE OF THE LIMITATIONS OF OUR OWN ON-BOARD RADAR IN PREDICTING TURB. JUST BECAUSE YOU DON'T SEE ANYTHING ON THE SCOPE DOESN'T MEAN THERE'S NOT SOMETHING THERE THAT CAN GIVE YOU A WILD RIDE AND MAYBE HURT SOMEONE.

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.