I am building a Sig Kougar, and am considering adding tip tanks. What effect will this have on the wing? flight characteristics?

I am also thinking about tapered ailerons, used as flaperons, to give it more of a swept wing look.

I did this on my Lil' Hornet and it perked up the roll rate considerably.

What do you all think?

Hello

Unless your building an airfoil thick enough to house the big spars you'll need, I wouldn't go with it unless decorative.

I believe the flutter those thing could create would force you to redesign the mounts and the spars and also even the wing joiner section.

Best Regards, Roderick Woolvett

First and foremost if you mean to carry fuel in them you're going to need to do some serious plumbing and provide for pumps. If they are to be just decorative then feel free.

Actually tip tanks can provide some benificial advantages by controlling the tip vortices. Of course just making something that looks good means any advantages will just be good luck rather than good planning but it's a hobby so do what puts a smile on yer face.

By tapered ailerons I gather you mean wider at the tip if they are giving the wing a swept look. No wonder they make it roll faster. You're putting more area out at the tips where it is more effective.

If you use the flaperons drooped for landing watch out for tip stalls with this reverse taper style. Being wider at the tip and then drooping them means you're adding more incidence at the tips. This is like having a whole lot of washIN rather than the usual tip stall controlling washOUT.

All the fighters I know of dropped their tanks before going into battle because of the adverse effect on maneuverability. Any additional mass at the wing tips will reduce roll rate. The mass of fuel out there will very seriously reduce roll rate.

Thanks for the input!

I was thinking looks not function, fuel tank in the nose.

With the tip tanks I am most concerned about negative aerodynamic consequences. I just like the way they look but they are not worth it if the plane becomes very difficult to fly. I can stand a reduction in roll rate. My plan is to carve them from a block of light balsa, slice it longitudinally and hollow it out then glue them back together.

I have read a lot in these forums about tip shape and how it affects flight characteristics. I am learning as I go. Is there a book that anyone would recommend regarding aerodynamics and/or design?

Yes, I was thinking the ailerons would be something like 1 inch at the root and 2.5 inches at the tip. I think I'll pass on this though, I had an intuition that they may produce negative effects although I didn't know what.

Boy-o-boy, I like this stuff!