Narrative:

Encountered severe turbulence during cruise portion of flight; near convective activity. There were two passengers on board. Prior to circumnavigating convective activity; we put the seat belt sign on; verbally requested [passengers] to fasten their seatbelt's including shoulder harness and visually confirmed compliance. Approximately 30 minutes later; we encountered severe turbulence and after stabilizing the aircraft after the event found one passenger belted in the seat and the other on his back in the aisle of the aircraft. After attending to the passenger and unsure about his condition we declared an emergency and landed at the closest airport with acceptable weather so the passenger could be attended to by paramedics. It was determined that he did not have serious injuries and was released. The passenger later stated; 'it is my own fault. I should have listened to you.' there is nothing a crew can do if a passenger decides to unbelt for comfort against the crews instruction and is hiding doing so under a blanket. I am certain that this passenger will always be belted in from takeoff to landing from now on.

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Original NASA ASRS Text

Title: Passenger on a C560XL did not comply with flight crew's request to fasten seat belt and shoulder harness and was injured when the aircraft subsequently encountered severe turbulence.

Narrative: Encountered severe turbulence during cruise portion of flight; near convective activity. There were two passengers on board. Prior to circumnavigating convective activity; we put the seat belt sign on; verbally requested [passengers] to fasten their seatbelt's including shoulder harness and visually confirmed compliance. Approximately 30 minutes later; we encountered severe turbulence and after stabilizing the aircraft after the event found one passenger belted in the seat and the other on his back in the aisle of the aircraft. After attending to the passenger and unsure about his condition we declared an emergency and landed at the closest airport with acceptable weather so the passenger could be attended to by paramedics. It was determined that he did not have serious injuries and was released. The passenger later stated; 'It is my own fault. I should have listened to you.' There is nothing a crew can do if a passenger decides to unbelt for comfort against the crews instruction and is hiding doing so under a blanket. I am certain that this Passenger will always be belted in from takeoff to landing from now on.

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.