Date: 201703
Local time of day: 1201-1800
Location: ZLA.ARTCC, CA
Flight conditions: VMC
Light: Daylight
Aircraft: B737 Undifferentiated or Other Model
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Cruise
Airspace: Class A ZLA
ATC / advisory: Center ZLA
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Second reporter function: Pilot Flying; First Officer
Anomaly: Deviation - Speed All Types; Inflight Event / Encounter Weather / Turbulence
Detector: Person Flight Crew
When detected: In-flight
Result: General Physical Injury / Incapacitation
Contributing factors: Weather
Primary problem: Weather

Narrative: Both pilots had their individual radar displays ON; as a precaution for possible weather avoidance; while departing.  There were no observable radar returns. Once at FL300; I checked with ATC about any enroute turbulence; and they stated there were reports of nothing worse than occasional light chop at our altitude and altitudes above. We were cruising just above; and near; the ragged tops of a cloud layer; in smooth air. The seatbelt sign was OFF. Just prior to the turbulence encounter; I had been entering a code into ACARS regarding an inoperative TCAS (TCAS FAIL) during climb; then cruise. We experienced a moderate turbulence encounter of brief duration; lasting approximately two seconds. I turned the seatbelt sign ON; and then it smoothed out quickly. Since it was already smooth again; over the PA; I had the Flight Attendants 'check in'; as opposed to 'be seated immediately; be seated immediately.' The lead Flight Attendant informed me of 'possible' flight attendant injuries; and spilled drinks on some passengers. I asked the Flight Attendant's to update me as soon as possible; but they were busy with assessing the situation; etc. By then; we were nearing the top of descent. Based on the information I had at the time; I requested Dispatch have EMS and Inflight meet the flight; due to possible Flight Attendant injuries. I did not have enough information to determine if declaring an emergency was necessary. I specifically did not request a link to Medlink; since we were about to start our descent; and didn't have enough information to pass along to them. Also; I have used Medlink on multiple occasions in the past; knew the connection would take several minutes; and be another unneeded distraction during the descent phase of flight. Dispatch requested more info on the turbulence encounter; and I told them it was moderate; and of its approximate location. I thought I had mentioned the moderate turbulence to Dispatch previously; but was very busy coordinating with the First Officer; the Flight Attendants; and the passengers; while managing my PM (pilot monitoring) duties. I then made a PA informing the passengers and Flight Attendants that EMS would be meeting the aircraft for anyone needing medical assistance. Additionally; I let the Flight Attendants know that Inflight would meet the aircraft as well. At the time of the moderate turbulence encounter; we also experienced an approximate 20 knot overspeed; of approximately two-second duration. I sent a code for that via ACARS; and later; debriefed local maintenance about the encounter. We blocked-in; EMS met the aircraft; and attended to the injured Flight Attendants. No passengers requested treatment by EMS. I had reviewed [the weather] for turbulence prior to departing. Based on that review; and ride-reports obtained from ATC; I felt it was safe for the seatbelt sign to be OFF; and for the Flight Attendants to be moving around the cabin. After block-in; I verified the Flight Attendants were receiving medical treatment; and made sure Inflight had my file number. I then turned my cellphone on; and called the [duty manager].


Second narrative: There were suspected injuries to two flight attendants in the rear jumpseats; but these were considered to be mild enough to not consider a diversion.


Synopsis: B737 flight crew reported two flight attendants were slightly injured in a moderate turbulence encounter during cruise.