JAL Express flight JA2375, an MD-81, took off from Osaka International Airport at 11:49 local time. While the aircraft was climbing at an altitude of 7,900 m, 80 km west of Osaka International Airport, the aircraft encountered turbulence and two cabin crew members were seriously injured. Cause This accident is presumed to have occurred because the aircraft, after taking off from Osaka International Airport and climbing with the seatbelt sign turned off, passed through a frontal zone manifested under the jet stream. As a result, the aircraft experienced significant turbulence due to strong wind changes, causing severe movement. This turbulence likely resulted in serious injuries to two cabin crew members who were working in the aft galley.