B757 Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 150; Flight Crew Total 30000; Flight Crew Type 4500
Inflight Event / Encounter Wake Vortex Encounter
General Physical Injury / Incapacitation
Environment - Non Weather Related; Procedure
Cruise climb stopped at FL330 by ATC for unseen traffic at FL340. Suspect crossed jetwash/wake turbulence. Sudden; very quick turbulence jolt encountered from smooth condition both before and after event. Flight attendants had just started service and were in aisle. 3 reported injured knee; wrist or back ache but declined medical assistance and continued flight to destination.
We had leveled off at FL330 in the vicinity of HACKS intersection and were awaiting further climb to FL340 once clearing crossing traffic at FL340. We were in clear air with no visual cues that turbulence was in the area (cloud formations; TS; etc.). I had asked for a ride report before turning off the seat belt sign and was informed that there were no adverse reports. The turbulence event was moderate in intensity with both lateral and vertical motions lasting approximately 1 second. I communicated with the F/As to determine if any passenger or crew member were injured. The F/A advised that no passenger appeared to have been injured; but that multiple F/As were experiencing physical discomfort as a result of the turbulence event.
B757 flight crew reported encountering wake turbulence at FL330 from an aircraft at FL340 that resulted in minor injuries to three flight attendants.