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Old 12th March 2007 | 20:47
  #21 (permalink)  
NickLappos
 
Joined: Apr 2003
Posts: 3,012
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From: USA
BIT, they aren't a bit alike, the old BERP blade has a thick, forward bulge at the tip that is almost ax-like when seen from above. In other words, the blade chord increases markedly at the tip.

The S-92 (and UH-60M) blade is a swept, anhedral tip that thins out in thickness and droops down the last 5% of blade span.

The S-92 blade has a figure of merit that is about 4% better than the BERP blade (which means that for the same horsepower, the S-92 blade lifts about 5% more weight than the BERP.)
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