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  #1  
Old 02-22-2017, 11:30 AM
RV8JD RV8JD is offline
 
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...........
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Last edited by RV8JD : 02-01-2019 at 10:25 PM.
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  #2  
Old 02-22-2017, 12:16 PM
Steve Barnes Steve Barnes is offline
 
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Talking Flutter demonstration (under laboratory conditions)

Take a piece of regular paper
Cut it 1/2" wide +- and about 4"+ long
Once the strip of paper is cut hold it between your thumb and first finger
Blow hard across the top of the paper

THAT MY FRIEND IS FLUTTER

Steve
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  #3  
Old 02-22-2017, 12:18 PM
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N941WR N941WR is offline
 
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This is "Flutter".

https://www.youtube.com/watch?v=qpJBvQXQC2M
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  #4  
Old 02-22-2017, 04:53 PM
rockwoodrv9 rockwoodrv9 is offline
 
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Bill, I have seen that video of the plane before, but seeing it again is still an eye opener. Wow. I can't see how those parts didnt break off. Maybe they did.
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  #5  
Old 02-22-2017, 06:33 PM
Neal Trombley Neal Trombley is offline
 
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Nasa did the test and stopped before any damage
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  #6  
Old 02-22-2017, 07:46 PM
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Bob Kuykendall Bob Kuykendall is offline
 
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Thanks, nicely done!
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  #7  
Old 02-23-2017, 09:56 AM
sblack sblack is offline
 
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That is a very highly technical definition. I think that could be simplified considerably to make it easier to grasp for the layman. I don't think most pilots would be able to visualize the concept of energy extraction from the airstream. I am not saying this isn't correct (I'm not actually sure) but I think most people would read that and their eyes would glaze over
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  #8  
Old 02-23-2017, 04:05 PM
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rv8ch rv8ch is offline
 
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Default Excellent!

Carl, this is really great, and has helped my understanding of the phenomenon. I think I understood it all, except why this is true:
Quote:
Originally Posted by carl
Not All Stiffness Increases are Beneficial for Flutter!
It makes intuitive sense, but it's not clear to me why.
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  #9  
Old 02-23-2017, 05:22 PM
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Quote:
Originally Posted by rv8ch View Post
Carl, this is really great, and has helped my understanding of the phenomenon. I think I understood it all, except why this is true:It makes intuitive sense, but it's not clear to me why.
Because increasing stiffness in one area can easily increase loads in another weaker area.
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  #10  
Old 02-23-2017, 05:58 PM
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DanH DanH is offline
 
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Quote:
Originally Posted by Mel View Post
Because increasing stiffness in one area can easily increase loads in another weaker area.
True for structure, but it's not a flutter factor.

Study pages 39 through 43 of Carl's very excellent presentation.
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