Date: 202102
Local time of day: 1801-2400
Location: ZME.ARTCC, TN
Flight conditions: VMC
Weather elements / visibility: Turbulence
Light: Night
Aircraft: Commercial Fixed Wing
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Cruise
Airspace: Class A ZME
ATC / advisory: Center ZME
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Not Flying
Reporter qualification: Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Human factors: Time Pressure; Situational Awareness
Second reporter function: Captain; Pilot Flying
Anomaly: Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Clearance; Flight Deck / Cabin / Aircraft Event Illness / Injury; Inflight Event / Encounter Weather / Turbulence
Detector: Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Provided Assistance; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Returned To Clearance; General Maintenance Action
Contributing factors: Weather
Primary problem: Weather

Narrative: Cruise flight at FL 390. Smooth air while overlying thunderstorms and VFR conditions. ATC authorized deviations left and right. Captain (CA) made PA call to Flight Attendants (FA) and passengers to all be seated and fasten seat belts. As the aircraft approached the far end of storm; severe turbulence rocked the plane and stick shaker and high speed warning activated twice. CA corrected and re-established control each time; but lost approximately 600 feet in so doing. Pilot Monitoring (FO) called FA's and FA1 reported FA2 was injured. They found her on the floor. FA1 asked for help from medical personnel and they responded. Destination was only 25 minutes away so we continued heading there in case medical attention was needed. Reported injury to ATC. Below 10;000 feet personnel in back advised paramedics were needed. Called for them to meet us at gate and proceeded direct to airport with ATC approval. Emergency vehicles were at the gate; but no ramp personal. FA2 was conscious but confused. She was taken to hospital. Dispatch and Maintenance contacted. I (Captain) called hospital from hotel and spoke to FA2. She was coherent but had no memory of any events previous to people talking to her from the passenger seat.


Second narrative: Captain was Pilot Flying. Cruise at FL390 with smooth air flying over a thunderstorm. Deviations left and right approved. PA call to FA's (Flight Attendants) and passengers to all be seated and buckled. Far edge of storm was in sight. Severe turbulence; as published; was encountered. Stick shaker activated twice and Hi Speed aural warning twice. Both times; stick shaker stopped quickly before throttles were advanced to maximum thrust. Loss of altitude approximately 600 feet. Control was re-established. Called FA's and heard FA2 was injured. They found her on the floor. FA1 asked for help from medical personnel; two nurses and one flight attendant responded. Destination was only 25 minutes away so we continued heading there in case medical attention was needed. Reported injury to ATC. Below 10;000 feet; personnel in back advised paramedics were needed. Called for them to meet us at gate and proceeded direct to airport with ATC approval. Emergency vehicles were at the gate. FA2 was conscious but confused and in pain from a hip. She was taken to hospital. Dispatch and Maintenance contacted. I (Captain) called hospital from hotel and spoke to FA2. She was coherent but had no memory of any events previous to people talking to her from the passenger seat.


Synopsis: Air Carrier Pilots reported severe turbulence encountered and a Flight Attendant injured.