Narrative:

I had deviated east of J89, south of iiu due to WX. I had the seat belt sign on and made PA's about expected bumpy air for a little while until we got past louisville. On the 25 mi scale on my radar, I waited until nothing painted ahead, and turned between returns. ATC reported light turbulence with occasional moderate. Encountered heavy precipitation, moderate turbulence, although no precipitation was painting on our radar. Hit one strong, sharp downdraft, aircraft fell 200 ft but autoplt stayed on. 2 passengers cut their heads on overheads -- they were not wearing seat belts in spite of 2 PA's from cockpit and 2 or 3 from flight attendants. We reported severe turbulence to ATC. We requested priority handling into ord due to passenger injury. A doctor on board said the passengers's head cuts were superficial although bloody. I believe my radar should have showed a return, especially on the shorter scales. Earlier, in the daylight, it gave us reliable information as we skirted WX over fl, and GA. There was nothing on our scope that I felt we needed to avoid. If seat belts had been fastened, injuries would not have occurred. If we had seen anything that looked serious on our radar, we would have avoided it. If nothing shows on the 25 mi range, it is not there. Given the same information from ATC, my radar, and my experience, there is nothing I would have done differently. I feel bad that anyone was hurt on my airplane.

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Original NASA ASRS Text

Title: 2 PAX WERE INJURED WHEN AN ACR LGT HIT SOME TURB. THE SEAT BELT SIGN WAS ON.

Narrative: I HAD DEVIATED E OF J89, S OF IIU DUE TO WX. I HAD THE SEAT BELT SIGN ON AND MADE PA'S ABOUT EXPECTED BUMPY AIR FOR A LITTLE WHILE UNTIL WE GOT PAST LOUISVILLE. ON THE 25 MI SCALE ON MY RADAR, I WAITED UNTIL NOTHING PAINTED AHEAD, AND TURNED BTWN RETURNS. ATC RPTED LIGHT TURB WITH OCCASIONAL MODERATE. ENCOUNTERED HVY PRECIPITATION, MODERATE TURB, ALTHOUGH NO PRECIPITATION WAS PAINTING ON OUR RADAR. HIT ONE STRONG, SHARP DOWNDRAFT, ACFT FELL 200 FT BUT AUTOPLT STAYED ON. 2 PAXS CUT THEIR HEADS ON OVERHEADS -- THEY WERE NOT WEARING SEAT BELTS IN SPITE OF 2 PA'S FROM COCKPIT AND 2 OR 3 FROM FLT ATTENDANTS. WE RPTED SEVERE TURB TO ATC. WE REQUESTED PRIORITY HANDLING INTO ORD DUE TO PAX INJURY. A DOCTOR ON BOARD SAID THE PAXS'S HEAD CUTS WERE SUPERFICIAL ALTHOUGH BLOODY. I BELIEVE MY RADAR SHOULD HAVE SHOWED A RETURN, ESPECIALLY ON THE SHORTER SCALES. EARLIER, IN THE DAYLIGHT, IT GAVE US RELIABLE INFO AS WE SKIRTED WX OVER FL, AND GA. THERE WAS NOTHING ON OUR SCOPE THAT I FELT WE NEEDED TO AVOID. IF SEAT BELTS HAD BEEN FASTENED, INJURIES WOULD NOT HAVE OCCURRED. IF WE HAD SEEN ANYTHING THAT LOOKED SERIOUS ON OUR RADAR, WE WOULD HAVE AVOIDED IT. IF NOTHING SHOWS ON THE 25 MI RANGE, IT IS NOT THERE. GIVEN THE SAME INFO FROM ATC, MY RADAR, AND MY EXPERIENCE, THERE IS NOTHING I WOULD HAVE DONE DIFFERENTLY. I FEEL BAD THAT ANYONE WAS HURT ON MY AIRPLANE.

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.