SAS Claims Bombardier Q400 Construction Error; Canadian Airframer Answers Back

SAS Group, which last year grounded its Bombardier Q400 fleet following three landing-gear incidents, issued a very bold statement this morning.

Clearly not mincing words, SAS says that, following a thorough technical examination of the turboprops’ landing gear, it found problems in 63% of the SSV valves on the inspected aircraft, and cannot be blamed for the undetected error that caused the first two accidents in the course of its maintenance work.

What does Bombardier have to say about all of this?

“There is no new evidence published by any investigation authority that alters the conclusions reached by the DAIB [Danish Accident Investigation Board] in its preliminary report, and the EASA in its statements, with respect to the cause of the O-ring blockage that prevented the main landing gear actuator from fully extending,” says the manufacturer.

“While investigations into Q400 main landing gear incidents continue, Bombardier will not comment or speculate on specific issues in isolation, such as the SSV valve, without the context of the final reports.”

Meanwhile, here is the full statement from SAS:

“We are waiting for the Accident Investigation Board’s final conclusion, and don’t want to speculate about the reason behind the third accident. We can confirm, however, that our technical department has found problems in 63% of the SSV valves on the inspected aircraft that we have permanently grounded after the accidents last autumn. SAS had no possibility of – and cannot be blamed for not – discovering these problems, or the undetected error that caused the first two accidents, in the course of its maintenance work,” says executive VP of corporate communications Claus Sonberg.

SAS adds: “The Danish Accident Investigation Board has previously concluded that a construction error in the actuators was the cause of the first two accidents involving a Dash 8 Q400. The Accident Investigation Board has not presented any conclusion on the reason behind the third accident, but has in a provisional report stated that the most likely reason is that an O ring came loose from the SSV valve in the hydraulics system in combination with the following fault-tracing. The SSV valve also has a construction error and is currently being modified by the supplier.”

SAS previously requested $77 million in compensation from Bombardier for costs and lost income associated with the accidents.

(Photo from Bombardier’s Q400 web page – which it might want to consider updating: )


Leave a Reply