Mini speedster wing mod question

[ShavenWookee]

I have a question: If I were to glue a piece of posterboard across the bottom of the wing to cover the cavity and create a flat surface, would that increase the lift of the airfoil? I thinking I would only install it to the part where the wing turns up. Im looking for more lift at lower speeds. A slow speedster, if you will. I know, don't judge, I'm off my meds today.

Anyone want to place any bets on how well this will work? I'm pretty sure unless I'm talked out of it, this is going to happen.

 

[quorneng]

The simple answer is no it won't.
The Mini Speedster has in effect an under cambered wing which is good for low speed lift. 'Filling' the underside so it is flat will give less lift at slow speed but should reduce the drag a high speed although the actual benefit will be small compared to the total drag created by the rest of the airframe.

 

[ShavenWookee]

And here I was with a glue gun in my hands and two cut pieces to plug those cambers. //slowly puts down glue gun and backs away...//
Really glad I thought "this feels dumb, perhaps I should check the post first." LOL

Thanks.

 

[mjmccarron]

You went this far. You could give it a try. The previous posts were right, The mod will reduce the slow speed lift considerably but it will also reduce drag. I don't think it will work but this is, in fact, Flite Test not Flight for sure. Experiments like these help us learn the effects of airfoil shape and drag. Without going to school for aeronautical engineering this is the best way to learn.

In any event, if you want to improve the performance of your Speedster, This is not the mod to do but it shows that you were thinking and that's a good thing!

Happy Thanksgiving!
Mike

 

[IFlyRCstuff]

What I would do is kimda complicated to explain, here goes. This will reduce drag, but remain undercambered and therefore high lift at slow speeds.
Cut a pice of foam the length of the inside wing (before the poly-hedral) and roughly 2 inches wide.
Then make a 50% cut down the middle to slighlty to one side, be sure it is parallel and perfectly straight, bevel it to match the undercamber of the wing and glue to the break in the wing
REPEAT ABOVE PROCESS if desired
Glue poster board across, going up to the double (or single) layer of foam board at the break. DO THIS WHILE MAKING THE BOTTOM AS ROUND AS POSSIBLE
It works because it is still undercambered, but it is smoother and therefore has less build up (eddies) at the break if done well.