New Winglets and Rudders

[borrisl]

Well, for reasons I don't want to talk about, someone has dropped some heavy items on the wings and split the winglets. This gives me the opportunity to build new ones (keep it positive).

Few questions for those who have experimented with winglets.
 

• I've heard through a friend that the original plans to mount the winglets caused a bit too much drag. What modifications have proven to be a drag reducer?
• What about producing the winglets and rudders out of carbon fiber? They are located in a place that seems that it could benefit from some additional stiffness?

[Marc Zeitlin]

1 hour ago, borrisl said:

Well, for reasons I don't want to talk about, someone has dropped some heavy items on the wings and split the winglets. This gives me the opportunity to build new ones (keep it positive).

• I've heard through a friend that the original plans to mount the winglets caused a bit too much drag. What modifications have proven to be a drag reducer?
• What about producing the winglets and rudders out of carbon fiber? They are located in a place that seems that it could benefit from some additional stiffness?

 

OK, so new the forum software doesn't easily allow for reasonable in-line reply formatting. Or if it does, it's not clear how to do it. Great. Onward.

First, why do you think you have to build a whole new winglet? From the single pic from a weird angle that you posted, it looks like the damage is concentrated only at the tip. If this is correct, then this is a few hours of non-structural repair work, and some cosmetics.

Second, my cousin's step-sister told me something once, but I didn't believe it. What makes someone think that the winglets are causing "too much" drag, and what does someone think would be better, and what would the ramifications of any proposed change be? Aerodynamically, and structurally? If you're not a structural or aerodynamic engineer, it's probably a bad idea to be changing aerodynamics or structures. There are many drag reduction modifications for VE's, LE's, COZY's and the like, and none of them involve changing the winglets. Blending, maybe. But not changing...

Third, what makes you think that the winglet needs to be stiffer? What problem are you trying to solve? What failures have occurred due to lack of stiffness?

[Kent Ashton]

I agree with Marc.  I replaced a winglet here  https://www.canardzone.com/forums/topic/18661-kents-long-ez-project/?page=3    It's a rather large job.  Yours looks quite fixable.

Edited July 25, 2018 by Kent Ashton