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ORIGINAL: Paul S.

What a great old thread, I am going to start on the wing saddle next weekend and remembered reading this thread but had two questions. I will add the positive 2 degree incidence to both; but #1. I lost you guys on the down thrust of the engine. I'm not sure if I need to change anything regarding that?

#2. I noticed watching a flying video of a Corsair in an airshow that the plane actually looks nose down as it's flying flat to the ground. I also wondered looking at the plan on the ground if the tail were to remain the same as a pivot point and I dropped the nose to look like the plane did in the video, it would be roughly an inch drop from end to end. That would mean raising the wing into the plane both front and back, I hope I said it so you could understand what I'm seeing. Would that be a way of changing the incidence or just raising the front main edge 3/16's and an 1/8th" front of the stab?

This kit is fun, but quite a first kit to start with. (Kinda like practicing learning to drive during an icy blizzard.)

Paul S.

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ORIGINAL: Rodney

I'm confused, if you change the incidence of both the wing and the stab the same amount, all you are really changing is the attitude at which the fuselage tracks thru the air and you have effectively only added down thrust by the amount you have change the incidence. The relative angle between the wing and stab have not changed unless you only change one or the other by itself. Why would not just changing the down thrust only do the same thing as changing both wing and stab angles by the same amount?

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Second when you change the Wing and Stab incidence the result will be that tail high look your talking about.

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ORIGINAL: BMatthews

Getting back to the wing and tail incidence angles for a brief moment in all this mutual admiration activity....

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Rocketman, you won't in any way make the model easier to fly or less easy to fly by making the wing and stab angles different as long as the stabilizer is a little more negative than the wing. Good flying charactaristics come from light weight and to a smaller extent a good airfoil that is weight tolerant plus some other bandaids like washout and high lift devices such as flaps. But the key element is and will always be the wing loading.

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So what sets the requirement for a particular wing to tail angular setting? That would be the CG location. The CG location dictates how much lift and what direction the tail needs to generate IN RELATION TO THE WING. Note the caps there..... If you try to "tame" something by altering the angular difference between the wing and stabilizer without changing the CG then all that happens is that you end up trimming the elevator to get the model to fly correctly until the resultant effective stabilizer/elevator combined angle is the same as it was before the change.

If you add +2 degrees to the wing and +2 to the stabilizer then all you've done is alter the thrust line to an additional 2 degrees more downthrust and now the model will fly just like before but with the fuselage angled tail up by 2 more degrees. The wing will always find the right angle of attack for any given airspeed and ignore any incidence changes you make to the model.

Where you'll gain is in making the model lighter (have I stressed that little fact enough ? ) and to some extent by using that Selig airfoil that has a proven track record for being a little more tolerant of heavy wing loadings. For a heavy model flaps is often a good option. Flaps do two things. First they add a lot of camber to the flapped portion of the wing and that means you can fly up to a higher lift coefficient for the flapped area. That normally translates to a slower but still safe approach speed which is obviously why the real ones used them. Second they greatly increase the angle of incidence over the flapped portion while leaving the tips the same as originally. This induces a HUGE amount of washout in the wing and really does make you work hard to achieve a disasterous tip stall. Mind you by the sounds of things in this thread there's no lack of pilots that are up to the challenge.....

Anyhow, Paul is 110% right. If it's heavy you ain't going to make it land like a feather. At best you can improve things enough to at least make it a little less scarey.