Date: 202106
Local time of day: 0601-1200
Location: ZFW.ARTCC, TX
Aircraft: Large Transport; Low Wing; 2 Turbojet Eng
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Descent
Airspace: Class A ZFW
ATC / advisory: Center ZFW
Second aircraft: Commercial Fixed Wing
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Second reporter function: First Officer; Pilot Flying
Anomaly: Inflight Event / Encounter Wake Vortex Encounter
Result: Air Traffic Control Provided Assistance; Air Traffic Control Issued New Clearance; Flight Crew Took Evasive Action; Flight Crew Requested ATC Assistance / Clarification; General Physical Injury / Incapacitation
Contributing factors: Procedure; Environment - Non Weather Related
Primary problem: Ambiguous

Narrative: On the SEEVR4 arrival FEWWW Transition to DFW descending from FL360 to FL340; in VNAV; smooth air; seat belt sign off; FO pilot flying we experienced wake turbulence from a preceding aircraft. The first encounter started with a light buffet typical of wake turbulence; then developed into a more severe rolling [motion]; and eventually rolled 15-20 degrees left disconnecting the auto pilot. The First Officer stabilized the roll; selected a shallow descent in vertical speed; and reengaged the autopilot. Shortly after; a second buffeting began and the aircraft rolled left again. The First Officer implemented unusual attitude procedures disengaging the autopilot; calling 'my aircraft' prior to the aircraft rolling to the extent it did in the first encounter. After stabilizing we asked for a lateral offset and reported the wake turbulence upset to ATC saying we were unable to avoid the aircraft's wake. It was granted and no further wake turbulence was encountered. I asked if the fight attendants were ok; which they responded 'yes'; and made a PA to the passengers. On landing; the No. 1 Flt attendant said that he hurt his neck trying to stay upright while standing in the aisle during the event. He had not fallen or hit anything but twisted it trying to keep his balance.I reported the event to Dispatch on landing.


Second narrative: During descent on the SEEVR4 into DFW leaving FL360 to FL340 wake turbulence was encountered. Preceding the event the aircraft was in smooth air. Approximately passing through FL350 the aircraft encountered the wake. A slight buffet was felt followed by a bank of approximately 15 degrees to the left. An immediate recovery was made. ATC was notified and the descent was shallowed to separate from the leading aircraft. This followed with a second less aggressive encounter and a full recovery was initiated. ATC was notified and we requested an immediate lateral deviation. No further wake was encounter for the remaining flight. The Captain made an announcement and talked to the flight attendants to verify everyone was ok. At this time he was informed no one was injured. Upon landing a flight attendant informed the captain that his neck was bothering him. Stating did not hit his head but may have twisted his neck and now felt pain.


Synopsis: Air carrier flight crew reported encountering wake turbulence descending through FL350 on arrival into DFW.