Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 193
Inflight Event / Encounter Wake Vortex Encounter; Inflight Event / Encounter Weather / Turbulence
General Physical Injury / Incapacitation
Environment - Non Weather Related; Weather
We encountered either clear air turbulence or wake turbulence at cruise altitude of FL400. We were not in any segmented areas and there were no adverse ride reports. Two Flight Attendants were thrown around and slightly injured. We had just inquired about the rides and were told occasional light chop by ATC. The Flight Attendants refused any medical attention numerous times. We asked; but requested removal from duty upon arrival at destination.
We leveled at our cruise altitude of FL400 and inquired ATC about ride reports several times. The report stated back was occasional light chop. We released the FAs to perform their duties. About five minutes later we encountered a 30 degree roll and 100 ft loss in altitude and what seemed to be wake turbulence or clear air turbulence. We were on top of a thin cirrus layer. I called back to check on the F/As and they reported that the B and C were in the back galley and were tossed around and received injuries.
B737 flight crew reported two Flight Attendants were slightly injured when clear air turbulence or wake vortex was encountered at FL400.