3/8" flaps?

I just realized that the TE of my wings are always thiker than 1/4".

I checked a 3/8 sheet of balsa and it was as light as a 1/4" one, and a LOT more rigid tyan the 1/4" sheets.

I'm going to use 3/8 flaps on my Vector .40 wing.

If it turns out nice I'll post the good (of not, the bad) news.

Gos bless you!

In Christ,

Ion, I don't think you'll have a problem with it if the piece is as light as you say. Always go for rigid flaps .
As an aside I just had a friend of mine come back from Brazil, Went down to meet his in-laws and he brought me a few magazines. He flies helis,
I have Aero&cia and Brazil Modelismo. Are these the leading RC publications in Brazil. Comparing the Real to the Dollar it dosn't seem too bad for products produced in your country but my friend said that a copy of RCM the leading RC magazine in the US would cost $24.95 US OUCH.
My Spanish is adaquate to figure out the Portugese and I see that a lot of familiar brand names are sold there also.
Dennis

>I just realized that the TE of my wings are always thiker
>than 1/4".
>
>I'm going to use 3/8 flaps on my Vector .40 wing.
>
>If it turns out nice I'll post the good (of not, the bad)
>news.
>
>Gos bless you!
>
>In Christ,
>
>Ion

Thick flaps can be good. However, I would strongly recommend that you do not allow the flap to be any thicker than the trailing edge of the wing. If you do, I would suggest that your turn will be "disappointing".

There are two reasons we use thinner flaps (and elevators):

1. The thinner moveable surface prevents early airflow separation. If your flaps turn out too thick, they will disturb the air coming off the trailing edge of the wing. Then you will be trying to deflect turbulent air instead of smooth air. As Keith mentioned, your turns will be disappointing.

2. The thinner surface has a little "wiggle" room behind the trailing edge. This may be more noticable at the back of the plane, but it allows the surface to move around slightly before it intrudes into the airstream. The airplane will seem much more stable. My hand can shake without the airplane shaking, too.

Remember that the air is flowing down the airfoil at the trailing edge of the typical NACA 0018 style airfoil and would come together at a certain spot behind the wing if we had no flap. If you taper the surface to approximate the airfoil, it will help.

There may be some other reasons, but these are the first that jumped into my mind. I hope the plane flies good for you.

Ron King