I have A question a person I fly with has a plane that flyes level and the tail is low and looks like the nose is flying a little up I know its A wing incidents problem some at the club say to increase the leading edge incidents I say increase the trailing edge incidents to lower the nose and bring up the tail I maybe wrong what do you all say michael

may not be a problem at all....

what kind of airframe?

it is not uncommon for an aerobatic airframe with a symmetrical airfoil to have to fly with a little bit of nose up angle of attack

its A high wing trainer

If incidence is the problem then leading edge up, an easy way to remember this is hold the wing level and decide what you need to do Ie; to move the nose down put a shim under the leading edge. Before you change the incidence I would first look at your balance. Depending on the level of the pilot it should balance level to slightly nose down at the mfgs. reccomended CG point with no fuel. Also look at the design, the old Midwest Aerostars and Stiks looked like they were flying tail low due to the horizontal stab being on the bottom of a downward tapered tail.

Yes if you set it up to be 0-0-0. The problem with this is that the engine thrust and stab are no longer paralell to flight path. This mainly effects uplines. Try setting the wing to +1/2 degree with everything else at 0. The fuse will then fly level and uplines won't tuck to the gear. well maybe not so noticable, I find that all my IMAC airplanes end up getting 1/2 degree upthrust.

Your friends are right... giving positive to the wing/stab/engine thrust in relationship to a fuselage datum line will raise the tail. Changing only the wing, changes the decalage (relationship between incidence of wing and stab) with the result of significant trim changes.

guess I was backwards in my thinking will try it this weekend as allways the people here on RCU are all knowing thanks michael

Look at it this way Michael, no matter what you do, the wing will fly at an angle to the apparent airstream just so that it exactly makes just enough lift to keep the plane in the air, fly slower it will need to be at a greater angle, fly faster it will need to be at a lesser angle. So, first decide what speed you mostly fly at. Look at the way the fuselage looks. Do you now want to 'lift the tail up?' Then you must adjust the angle of the fuselage to the wing so that with the wing held still the tail raises, you will see now a gap between the front of the wing and the fuselage (high wing). Fit a packer to maintain this angle. Unfortunately this also changes the angle between the wing and tailplane, the 'speed trim' of your model. You must now return this angular difference to what it previously was. There are two ways, one, by re building the tailplane angle to match the previous set up, which will involve some surgery to the fuselage, or do what most of us do, re-trim the flying bit (elevator trim) so that aerodynamically the effect is the same. This will likely involve a bit of down trim. You will notice that there is no need, or requirement, to alter the balance of the model. And in fact you should not, assuming that you are happy with the balance as it is.
Evan, WB #12.

Adding positive incidence to the wing will "raise the tail", but that is a small visual aesthetic gain against the change in flight characteristic cause by changing the relative incidence between the wing and horizontal stab. It is a trainer, leave it alone!

Bedford

The plane is just trying to tell his owner that it doesn't want to be a trainer any more, it wants to become a 3D plane......

Hahaha, good one Commbatpigg....

Cheers


Bundu