Corrosion found after SAS Q400 gear collapse

Exercise 7.1 Read and translate the text.

Danish investigators have identified corrosion in the main landing-gear assembly on the Scandinavian Airlines Bombardier Dash 8 Q400 that suffered a gear collapse during an emergency landing at Aalborg on 9 September. Corrosion on the internal threads of the starboard main-gear actuator piston, which controls gear deployment, led to the piston’s rod end becoming detached from the piston.

The Danish accident investigation agency HCL says that “ the separation contributed to the landing gear collapse”. The main landing gear on the Q400 retracts rearwards into a cavity behind the engines. The agency says that damage to the actuator piston can cause the undercarriage to deploy too quickly.

Three days after the Aalborg incident a second SAS Q400, destined for Palanga in Lithuania, suffered an apparently similar main landing-gear collapse.

Canadian regulators have issued an airworthiness directive requiring landing-gear inspections on Q400 aircraft that have accumulated more than 8000 cycles or four years service.

SAS and Norwegian sister operator Wideroe have withdrawn their Q400 fleets pending inspection, while other operators have examined older aircraft.

Corrosion found in more SAS Q400s