New Member

[Samothy12]

Hello all!

Although I am a new member and this is my first post, I have been following this forum for quite some time. In the past, I have built a number of Guillows models, although not all of them were successful. Soon I will start building my 500 series Hellcat and will no doubt have many questions. For now, though, I would like to ask the following:

- What is washout?
- What effect does washout have?
- How can I add it to my models?

[Wildpig]

Hi Sam,
Welcome and thank you for deciding to post messages. The more the merrier.

Washout: a fixed twist in the outer wingspan that lowers the angle of incidence of the outer portion compared to the main part of the wing. Works like this: the main portion(from the fuselage to lets say about 3/4 of the way to the tip) of a wing is flying along at 12 degrees angle of attack (close to it's stalling angle). The outer portion of the wing is twisted in such a way that it's angle of attack is 9 degrees (for example). For whatever reason, gust of wind or control input, the plane noses up,and the main wing stalls, let's say at 13 degrees. The outer portion of the wing is experiencing only 10 degrees of angle of attack, so is still flying and producing lift. What this does to the airplane is keeping it from rolling over in a stall. If the outer portion stalled first, there is not much roll control.

Adding washout: I add washout by putting a shim under the trailing edge of the wing when I building the wing on the board. Mitch, did it when he put the tissue on the wings by shrinking the tissue on the top of the wing, first.

Adding pictures: look at a recent post on this forum. I think BillParker explained how to do it. There are two methods. I haven't posted pictures, so I can't say what works.

[Wildpig]

All those terms, angle of attack and incidence might be unknown to you. Here is a link that shows some of what I"m saying.
http://www.insideracingtechnology.com/t ... attack.htm

If you use the Search... feature on the Guillow forum for the word "washout", you can find out more information.

[Samothy12]

Thanks Wildpig!

[Mitch]

Hi Sam,

I used magnets, altough you could use anything to get that washout. When I built my wing I wet it, I really soak it. Don't know that you have to do that, but that is what I do.



Let it dry for about 15 minutes it was still wet and very plyable, then set the washout with the magnets



When the wing dryed it had the washout and the wrinkles were gone!



This model is showing promise to be a good flyer and I still have yet to pack it with rubber and get the most out of it. When you fly you will also need a trim tab on the port wing and a bit of down thust on the propeller. The model without the trim tab will turn to the left with the tork of the spinning prop and spiral into the ground!



Good Luck Flying

Mitch

[Samothy12]

Hi Mitch!

Thanks for the photos! Along with Wildpig's post, they will be extremely helpful!