A de Havilland Canada DHC-8-4012Q (Dash 8) was operating a domestic flight between of Osaka-Itami Airport and Kochi Airport, both in Japan. Onboard a crew of four (2 flight crew & 2 cabin crew) and 57 passengers.
The aircraft before recovery from the runway (© ARAIC)
At 08.21 lt the aircraft lifted off from the Osaka runway for the short flight to Kochi (According to the flight plan 41 minutes), with the Captain as pilot monitoring and the co-pilot as pilot flying. After a short cruise, the aircraft was established on the approach for runway 32 at Kochi and received its landing clearance.
When configuring the aircraft it became apparent that the nose landing gear would not extend. ATC was informed accordingly and the aircraft entered a holding pattern to complete the necessary checklists and troubleshoot the problem. During the time in the hold After 25 minutes in the hold, the crew requested to perform a pass over the airfield at 500 feet so ground staff could visually check the situation. Two low passes were made and it was clear that the nose landing gear bay doors were closed.
The aircraft, shortly after the accident (© ARAIC)
In an attempt to extend the nose landing gear a steep turn was flown, but to no avail. The gear remained up, with the gear bay doors closed. The next request from the crew to ATC was to carry out a touch and go, in the hope that it would free the gear. ATC approved the request but also the touch and go did not free the gear from its enclosure in the nose landing gear bay. With all attempts unsuccessful the crew requested landing clearance. ATC cleared the aircraft to land on the foam-covered runway.
The aircraft touched down at 10.54 lt in the touchdown zone and came to a stop halfway down the runway.
An investigation into the accident was launched by the 'Aircraft and Railway Accidents Investigation Commission (ARAIC) of Japan. (Their final report is available by clicking here) The reason for the failure of the nose gear bay doors to open lay in the fact that a bushing migrated blocking the door movement. The bushing could migrate as the nut and bolt holding the bushing in place was missing. The reason for the bolt and nut to be missing is not clear in the report from the ARAIC, it literally states: "it is considered that these parts were not re-installed at the time of the repair in the manufacturing process of the Aircraft."
The displaced spacer (bushing), causing the gear failure. (©ARAIC)