Incident Overview
On January 8, 2020, at approximately 10:01 JST, an ATR 42-500, registered JA07JC, operated by Japan Air Commuter Co., Ltd., ran off the side of Runway 03 at Amami Airport in Kagoshima Prefecture, Japan, during landing. The aircraft came to a stop on a grassy area beyond the runway side stripe marking and was disabled to perform taxiing. There were 21 persons on board—the captain, first officer, and 18 passengers—and no one was injured. The airport was closed until 23:24, resulting in the cancellation of 37 scheduled flights.
Flight History
The aircraft was operating a scheduled flight from Kagoshima Airport with stops at Amami, Kikai, Amami again, Tokunoshima, Okinoerabu, and Naha. Before departure, the flight crew predicted strong northwesterly winds after a frontal passage. The aircraft departed Kagoshima at 07:29 and landed normally on Runway 21 at Amami at 08:28. After a flight to Kikai Airport, it departed Kikai at 09:53 as flight 3830, flying back to Amami at 2,000 ft under visual flight rules. The captain occupied the left seat as pilot flying, and the first officer served as pilot monitoring.
Approach and Landing
The captain planned a landing on Runway 03 with flaps at 35° and an approach speed of 105 kt. The approach briefing did not include crosswind landing information. At 09:54:31, the radio reported wind from 320° at 28 kt, gusting to 38 kt. The captain judged a landing was feasible as the crosswind component was within company limits. During the approach, the aircraft speed fluctuated multiple times below or above the target speed due to varying winds. The first officer called out each speed deviation. Although the captain considered a go-around, he believed stabilized approach criteria could be met with corrective maneuvers. At 09:59:37, the radio reported wind from 310° at 27 kt, gusting to 38 kt.
The aircraft passed over the threshold at about 50 ft AGL with a left bank of approximately 4° and a magnetic heading of about 023°. Right rudder was applied at about 30 ft AGL, and nose-up elevator at about 20 ft. The aircraft touched down left main wheel first near the runway centerline at about 400 m from the threshold, with engines at flight idle and rudder pedals nearly neutral. Approximately one second later, all landing gear weight-on-wheel signals indicated ground mode.
Post-Touchdown Events
Around touchdown, the captain was heard on the CVR saying, "USE THE AILERON SUFFICIENTLY TO THE LEFT." About one second after touchdown, the captain initiated reverse thrust after verifying propeller pitch. The aircraft began to bank right, and the control wheel input increased leftward, but the right roll angle increased to about 5°, and the magnetic heading changed to about 019°. The weight-on-wheel signal of one main landing gear temporarily reverted to air mode. About three seconds after touchdown, the captain fully applied the right rudder while maintaining reverse. The heading began to move toward the runway centerline after reaching 011° about four seconds after touchdown. The captain continued using right rudder, nosewheel steering, and right brake only. The first officer managed the control wheel and pushed the control column nose-down, but a right bank persisted until about six seconds after touchdown. After control transfer, the first officer noticed the aircraft moving left but believed the captain could correct sufficiently. However, the aircraft departed the runway into the grassy area on the left side and stopped, unable to taxi.
Investigation
The Japan Transport Safety Board investigated the serious incident. The flight data recorder and cockpit voice recorder were analyzed. The report details the flight crew's actions and the aircraft's responses. No probable cause is stated in the report.