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rcav8r2
Aug 01, 2007, 01:47 PM
Not sure if this is the right forum, but....
For years (about 10) I flew a modified (1/2 dihedral, ailerons, flaps, way more power than it needed)Kadet Senior. I gave the plane away when I switched to electric as it would have been too expensive to convert to electric ( back in 2002ish) and it was VERY fuel soaked.

Anyway now that is with in reason to (over)power a plane of this size, I was thinking about building a new one over the winter.
Well one of the things I loved about the plane was how well it side slipped. I would come in all bent out of shape, land on one wheel and drag a wingtip down the runway (I had wheels in the wing tips) on a touch and go, etc.

So I got to thinking... Why not design one that would side slip better. Been flying a modified Kadet LT25 since 2003 as fix for the larger Kadet, but it doesn't slip nearly as well.

Question is, what makes the plane side slip so well?
Fuse area, tail moment, etc?

Any and all suggestions would be greatly appreciated.
Thanks

Ollie
Aug 01, 2007, 02:40 PM
Making it flying more side ways (yawing) means more rudder control power. Use more rudder throw and rudder area. If you need enough anti-roll control power (flying level) too then improve aileron throw and aileron area near the wing tips.

JetPlaneFlyer
Aug 01, 2007, 04:19 PM
You will not want the model to have much lateral stability otherwise it will tend to roll with yaw... So a model with mid wing and no dihedral should work well. Minimal fuselage side area would help too. As Ollie said a nice big rudder would be a must with a small fixed fin area. If it had it's rudder area distributed as evenly as possibly above and below the fuselage centre line that may help remove any roll couple effect.

Steve

DT56
Aug 01, 2007, 05:41 PM
text

rcav8r2
Aug 02, 2007, 12:15 AM
Thanks for the responses... I was planning on something in the neighborhood of 80" (basically scaling up a Kadet wing) and aileron cord of about 25% cord, and length of 66% of that wing half past the fuse ( flaps for the rest the other 33%) as this was like my Kadet.
So a bigger rudder will help here, I was thinking that, but good to know for sure. Actually I like the roll coupling of the high wing so I'll keep that. Good to know how that interacts, so I can design for what I'm looking for. Part of the fun for me is cross controlling.
Interesting about smaller fuse area... I was thinking larger...for more drag. But I guess you are saying smaller fuse area will let it yaw better? If so, this is the way I'll go.

DT, yea the Fancy Foam Edge sure does slip really well ( knife edge hover on the deck touching a wingtip, into a slight breeze is a blast), but I am looking for something a little more ridged than a flat plate foamy... at 8' the flex would be unreal :)

Gene Bond
Aug 11, 2007, 07:51 AM
... but I am looking for something a little more ridged than a flat plate foamy... at 8' the flex would be unreal :)

Just use 1" thick sheet :)