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Old 15th Sep 2006, 01:23
  #10 (permalink)  
IFMU
 
Join Date: Mar 2005
Location: Poplar Grove, IL, USA
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Originally Posted by Graviman
I'm slightly suprised there isn't a groove designed into the extrusion for the top & bottom skins to tuck into. The skins look like aluminium to me. The discontinuity could then be sealed, to avoid tripping up the air flow. It just strikes me that bonding without some means to avoid peeling failures will at best limit design life.
Mart
Mart,

Robbies aren't the only ones with blade construction like that. Enstroms also have an extrusion in the nose (solid, heavy) and a top and bottom skin bonded on. Both the robbie and the enstrom have a step in the extrusion so the aluminum skin is flush with the nose, so it doesn't trip up the airflow unless it looks like the one in the beginning of this thread.

In my co-worker's collection there is also a metal bell blade, from a 47 I think. It has similar construction but then there is a skin that wraps around the nose up to about 1/4 chord or less. There is also a 300 blade, and that's like a 1-piece taco skin that wraps all the way around the extrusion in the front. Pretty nice design if you ask me.

I've heard some people say that "If it stays together it was bonded. If it comes apart then it was glued."

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