PPRuNe Forums - View Single Post - EC225 crash near Bergen, Norway April 2016
Old 17th May 2016, 09:40
  #749 (permalink)  
Colibri49
 
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n305fa


According to what I've researched on Google, there is a dedicated "epicyclic module chip detector" which you describe above as "not very efficient, small size, big epicyclic case radius" which is generally correct. What I myself saw when the conical housing and top of the gearbox got dismantled to remove the ring of magnets, was a lip right around the edge of the tray to which the magnets were attached.


There was a gap of 1 or 2 cm in this lip to allow oil draining down from the epicyclics to get "focused" into a narrow stream passing over the epi chip detector below the gap (engineers please correct me if I'm wrong), thereby increasing the chances of metal particles getting detected.


So if that lip with a gap is still part of the tray's design and now that the ring of magnets is no longer in place, even the slightest particle from the epicyclics and mast area would be detected at a very early stage and long before the risk of a catastrophic break-up might occur. I can't accept the idea of only one or two particles being detected by this improved system (without magnets) followed by a sudden break-up?


Hence my question for the 3rd time "Was there any history of the Norwegian EC225 gearbox making metal before the crash, because if not the likelihood of similarity with REDL is probably reduced?"
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