What happened
On the scheduled service flight NU611, an aircraft departed Naha Airport at 13:09 local time bound for Ishigaki Island. The flight was carrying a total of 138 people, consisting of 133 passengers and five crew members. During the approach to Ishigaki Airport, the flight crew followed instructions to descend from 24,000 feet through 8,000 feet down to 3,000 feet for landing on Runway 22. At the time of arrival, weather conditions indicated a temperature of 32° C and winds originating from 300° at 12 knots.
The landing sequence involved a bounce followed by a second touchdown. The aircraft touched down with a speed approximately 6 knots higher than the reference speed (Vref) amidst crosswind conditions. During the rollout, the spoilers and thrust reversers appeared to be non-functional. In response, the crew proceeded to shut down both engines, an action that prevented the use of the anti-skid system. This led to the simultaneous bursting of the inner tires on both main landing gears while the plane was 125 meters from the runway threshold. The aircraft then veered left and overran the runway, coming to a stop 145 meters beyond the end of the pavement.
While all 138 occupants successfully evacuated the plane, 49 individuals sustained injuries. Approximately twelve minutes after the excursion, an explosion occurred in one of the engines, which subsequently ignited a fire that partially destroyed the aircraft.
Findings
- The decision to shut down both engines during the landing roll rendered the anti-skid system unavailable.
- The loss of anti-skid functionality contributed to the tire failures and subsequent loss of directional control.