Kitfox Mk2 wing rebuild

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Posted

Hi everyone,

I will soon be rebuilding the wings from my Mk2 Kitfox and wondered if there are any fixes or mods I could incorporate to make it fly better ?
I have read about optima wing kits and sticking a plastic former on the front spar and speed wing conversion but I don't know exactly what this involves.
My aircraft is currently registered as a 3 axis microlight so I have to keep within the rules for stall speed etc.

Also, I have noticed that in my 4 wings, I have 2 types of spar, one is an aluminium extrusion tube with a central section (like 2 back to back capital D's), this runs all the way along the wing.

The other type is an aluminium tube with an insert inside it to mimic the one piece extruded one, the insert starts just before the lift strut attachment point and runs to the end of the wing.

Any ideas which one is better ?


Any ideas or input would be really helpful.
Cheers,
Skelly.

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Posted

Sounds like a standard Model 2 wing spar. About all of them had the spar insert. Only mod I would make is to reinforce the rib tails per the manual.

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Posted

For a while Kitfox went with the aluminum extrusion for the wing spars.  Late Kitfox 1s and Kitfox 2s had it.  When the Kitfox 1 used that type of spar, the gross weight was raised from 850 to 950 lbs.   On a tube spar, it much depends on what the stiffener is like.  The later Kitfox models used a .058" spar, and had the gross weight at something like 1400 lbs.  The .065 spars are used up to 1550 gross weight.  Like I said, it all depends on the stiffener.  My understanding is the stiffener was always centered on the lift strut attachment point.  I wouldn't doubt that the extruded spar makes for a stiffer wing.  I think either one will work though if you stay with the 950 goss weight.  Rib tail reinforcement is a good idea like Allen said.  Actually I think it may be required in your country.  The plastic leading edge that Kitfox 4 and later use is actually part of the rib design. It may not do much for the undercambered wing like the Kitfox 2 has.  JImChuk

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Posted

I´m also rebuilding my wings for my KF 2, i have bought new spars and inserts from Kitfox and i hope tu use most of the materials from the old wings. I´m rebuilding because of damage to the spars.

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Posted

Interesting stuff,

I looked down my spars on my orange wings th/at have the separate insert and was quite shocked to see that the stiffener web is not vertical where you would expect  it to offer max strength.

I don't know who built it that way but I'm glad I never flew in it.

The spars on my blue wings are the one piece extruded type but both front spars are damaged, the 2nd spars seem good though, 

I measured the twist on these wings at 1.5 inches.

I have 6 brand new full length one piece spars so I should be able to use some of those to fix up my blue wings.

I'll try and post some photos.

@Peter_se how much wing twist are you using ?

Cheers,

Skelly.

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