Narrative:

We were in level cruise at FL230 approximately 85 mi southwest of razorback VOR. Flow control had rerted us on a west to northwest departure for a northeast destination. There was a huge cell over mcalester VOR north of dallas that had spawned some reported tornadoes. Our radar was functional and we were well clear of the cells in the area. In the clear as we were about to leave an area that looked like it was unstable, the aircraft was hit by a severe jolt of approximately 2 second duration. I estimate we pulled a momentary (1/2) positive G followed by a (1) negative G. Nothing before or after. Flight attendant called up to the cockpit and said several passenger had hit their heads on the ceiling and there were some panels falling down. We called ahead and requested medical assistance and a mechanic to meet us upon our arrival at fyv. Rest of flight and landing was uneventful. One passenger complained of neck pains and she was taken to a hospital where x-rays were taken. She was later released. The seat belt sign had been on the entire flight and the flight attendant had just done a compliance check. In my review of actions that were taken, I can't see anything that we could have done to avoid the situation, with the exception of not flying on a day when the convective activity was high.

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Original NASA ASRS Text

Title: SEVERE TURB CAUSED PAX INJURIES AND ACFT CABIN DAMAGE TO ACR LTT TURBO PROP DURING CRUISE.

Narrative: WE WERE IN LEVEL CRUISE AT FL230 APPROX 85 MI SW OF RAZORBACK VOR. FLOW CTL HAD RERTED US ON A W TO NW DEP FOR A NE DEST. THERE WAS A HUGE CELL OVER MCALESTER VOR N OF DALLAS THAT HAD SPAWNED SOME RPTED TORNADOES. OUR RADAR WAS FUNCTIONAL AND WE WERE WELL CLR OF THE CELLS IN THE AREA. IN THE CLR AS WE WERE ABOUT TO LEAVE AN AREA THAT LOOKED LIKE IT WAS UNSTABLE, THE ACFT WAS HIT BY A SEVERE JOLT OF APPROX 2 SECOND DURATION. I ESTIMATE WE PULLED A MOMENTARY (1/2) POSITIVE G FOLLOWED BY A (1) NEGATIVE G. NOTHING BEFORE OR AFTER. FLT ATTENDANT CALLED UP TO THE COCKPIT AND SAID SEVERAL PAX HAD HIT THEIR HEADS ON THE CEILING AND THERE WERE SOME PANELS FALLING DOWN. WE CALLED AHEAD AND REQUESTED MEDICAL ASSISTANCE AND A MECH TO MEET US UPON OUR ARR AT FYV. REST OF FLT AND LNDG WAS UNEVENTFUL. ONE PAX COMPLAINED OF NECK PAINS AND SHE WAS TAKEN TO A HOSPITAL WHERE X-RAYS WERE TAKEN. SHE WAS LATER RELEASED. THE SEAT BELT SIGN HAD BEEN ON THE ENTIRE FLT AND THE FLT ATTENDANT HAD JUST DONE A COMPLIANCE CHK. IN MY REVIEW OF ACTIONS THAT WERE TAKEN, I CAN'T SEE ANYTHING THAT WE COULD HAVE DONE TO AVOID THE SIT, WITH THE EXCEPTION OF NOT FLYING ON A DAY WHEN THE CONVECTIVE ACTIVITY WAS HIGH.

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.