PPRuNe Forums - View Single Post - Bell/Lockheed and Sikorsky/Boeing Selected for JMR-TD
Old 11th Oct 2018, 03:55
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SplineDrive
 
Join Date: Feb 2015
Location: USA
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My experience with automated fiber placement is such that I would not recommend it for a one off aircraft. Rather, design the blade so that it can be automated, but hand make the demonstrator. The 429 construction techniques work well for a conventional helicopter blade, but perhaps aren’t as appropriate for a thick, torsionally stiff tiltrotor blade.

In any case, I would never have suggested SB>1 use AFP for a demonstrator blade. I suspect that wasn’t the only delay, but I know the struggles the team would need to overcome to AFP a long blade spar like the article implies.

Hope we see more information soon. Will be interesting to see if the flight vehicle matches the renders we’ve been seeing for years.

Originally Posted by SansAnhedral
Apparently SB-1 is now "complete" minus blades! If that truly is the case, I cant understand why the media reporting on this hasn't leaned on Boeing to release some pictures. Bell basically gave the media a build log from the earliest stages, yet the aviation press seems content to show the same CG renderings of Defiant over and over for 3 years. You would think they would at least get Boeing on record explaining why they want to keep it under wraps when their competition is flying almost daily.

The blade fabrication issue seems especially interesting, as I understand that Bell specifically went away from Automated Fiber Placement and toward broadgoods on V280 due to their experience on 429 and 609 fiber placed production blades. Must have been interesting to the Army to be briefed by one competitor that a specific manufacturing technology was less desirable, while the other was struggling for years behind closed doors (supposedly delaying the whole program) trying to make it work.

https://www.rotorandwing.com/2018/10...t-main-rotors/
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