I built an Eindecker looking thing.

Click on the numbers to the left, of the photo , under "temp" for more views.

http://antiqueradios.com/gallery/v/temp/026.JPG.html

The span is 9' (2052 sq inches) the loading comes out to 27oz/square foot. The gross weight is 22-pounds. The engine is a 41cc koirtz from a chainsaw. IT turns a 20 x 8 at 7100. The wing, elevator and engine are all on the centerline. Right now I have the thrust angles at zero down thrust and no side thrust. I was thinking of just programing those corrections into the radio. The idea is to mix the throttel with the elevator and rudder to make it fly straight regardless of throttel position.

Good idea??

Hey, I don't have a good way to test how much thrust a 22x8 at 7100 rpm makes. Anyone got a guess?

To be honest, using the radio is a Really bad idea...

You should consider putting the adjustments into the engine mount if you want the plane to track smoothly in flight. There is another post that discusses this and there is a website that you may wish to view that gives a calculation on how much offset to build in. You will need to hunt around as it is an extensive web site. The link below should put you in the neighborhood.

http://www.airfieldmodels.com/inform...propellers.htm

The post I am referring to is:

http://www.rcuniverse.com/forum/fb.asp?m=8678975

Mick...

You don't necessarily want down thrust in every plane. Thrust angles are going to be dependent on the location of the wing.

For example:
Most high wing trainers require 2* or even 3* down thrust. This is because the wing on top creates airframe drag on top. The leading edge of the wing is drag and it's on top of the fuselage. So as the leading edge of the wing is pushed back from drag, it causes the front of the plane to pitch up. We use down thrust to counteract that.

Now take a look at a low wing plane such as an Extra 300L. The engine thrust line is higher than the wing. The wing is on the bottom of the plane so leading edge drag will cause this plane to naturally pitch down in the nose. You want 0* thrust or even 1* UP thrust in a plane like this.

For a shoulder wing, I'd probably set it to 0* down thrust and adjust after I fly it. Look at a Laser 200 or an Edge 540. Most of those planes will have 0* up/down thrust because they are mid/shoulder wing planes. The engine, wing and stab are all lined up pretty close on the thrust line.

I can visualize what you are saying. So, in my case with the prop hub and wing right on the centerline, I guess I will try 3-degrees right and no down as a start. Thanks.