Date: 201405
Local time of day: 1201-1800
Location: ZKC.ARTCC, KS
Flight conditions: Marginal
Weather elements / visibility: Thunderstorm; Turbulence
Light: Daylight
Aircraft: Citation Excel (C560XL)
Operator: Fractional
Operating under: Part 135
Mission: Passenger
Flight phase: Cruise
Airspace: Class A ZKC
ATC / advisory: Center ZKC
Reporter organization: Fractional
Reporter function: Captain; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Anomaly: Flight Deck / Cabin / Aircraft Event Illness / Injury; Inflight Event / Encounter Weather / Turbulence
Detector: Person Flight Crew
When detected: In-flight
Result: General Maintenance Action
Contributing factors: Human Factors; Weather
Primary problem: Weather

Narrative: During preflight weather check for flight to APA; we talked to Dispatch about our filed route and the line of thunderstorms to the west of our route. Dispatch and I agreed to refile a new route to the north of BUM to circumnavigate the line of thunderstorms before turning westbound and added additional fuel. During the passenger safety brief; I advised passengers of our plan and that we might have turbulence so make sure seatbelts were secured and adjusted well. After takeoff during climbout; we advised Kansas City Center of our plan and he said about 10 aircraft had just done the same thing and it had worked out well. We flew northbound on the east side of the line of thunderstorms and leveled at 40;000 FT. We requested and were approved heading deviations for weather avoidance. We turned westbound and crossed the line of storms with the largest radar returns about 35 miles south of us. We were right in the tops of the clouds and could see blue sky above. We requested wrong direction 41;000 FT but were unable due to traffic. We then encountered a short burst of severe turbulence. The autopilot disengaged and we had a red flashing Master warning but no other annunciators. We re-established aircraft control; and reset seat belt sign to on. The largest altitude deviation I observed was about 200 FT high and aircraft heading changed about 20 degrees to the left. We checked on passengers and one who didn't have seat belt secured said he hit his head on the ceiling twice. We asked if he was okay and wanted to divert for medical attention. He said to continue on. The flight continued to destination uneventfully. After landing; the passenger advised us he was going to have his driver take him to be evaluated at a medical facility. We post flighted the aircraft with no noticeable discrepancies and entered a maintenance write-up in the log for a Severe Turbulence Inspection. It would be nice to be able to use aircraft wi-fi to update weather radar once enroute to see how storms are moving or changing and get an updated big picture on the situation as weather changes rapidly and new storms had probably formed since we had been airborne 30 minutes plus start and taxi time. It would be nice if company dispatchers also could track us better and keep us informed of changes during challenging weather. We made the mistake of thinking we had already passed the line of storms and that no other significant weather was along our route. Our airborne radar didn't indicate any severe looking storms once we passed the line north of BUM. We were actively using the airborne radar and didn't observe any severe storms when we encountered the severe turbulence.




Synopsis: CE560 Captain reports a severe turbulence encounter at FL400 while navigating around a long line of thunderstorms. One passenger who was not wearing his seatbelt was injured. Flight continues to destination.