Preliminary conclusions into a Wideroe Bombardier Dash 8-100 gear-collapse accident at Sandnessjoen, Norway, point to a sudden loss of height in the last moments before touchdown, as the turboprop attempted to land in blustery winds.
The aircraft, arriving from Bodo, sheared a fuse pin in its right-hand main undercarriage during the impact, breaking the gear and causing the aircraft to slide about 300m along runway 03.
Initial findings from Norway's SHT investigation board state that the crew checked the airport's weather data three times in the 12min before landing, each report showing highly-variable winds for both runway directions.
Two minutes to landing the wind for runway 03 was from 110°, varying from 080-150°, with a speed of 9-15kt. The airline's wind limit for the approach was 15kt if the wind direction was 060-150°.
The crew flew a short final approach and was established in landing configuration about 280ft above the runway, according to flight-data recorder information.
Just before touchdown the aircraft was "suddenly exposed" to a gust of wind and its descent "increased significantly", said SHT. Flight data showed strong right aileron input and, about the same time as the radio altimeter registered the height at 20ft, the aircraft struck the ground about 150m after the threshold.
"The aircraft bounced slightly and, with the next contact, sank with its right wing low," said SHT, adding that the pilots successfully kept the aircraft on the runway.
Inquiries into the landing, exactly a year ago, found that the fuse pin in the right main landing-gear had fractured from excessive loading. SHT said the pin is designed to shear, sacrificing the undercarriage in order to reduce the risk of wing and fuel-tank damage, and to retain a degree of directional control.
Only three passengers were on board, as well as four crew members. An experienced SAS Group pilot was flying the aircraft on his third day of training as a candidate captain for Wideroe.