Kitfox 3 wing change.

[foxkit3]

Hello.

I'm looking to get some more speed out of my kitfox 3. I have a 912 ul with a ivo in flight adjust prop. I can reach the v.n.e very easly. I know it is not common practic to fly over v.n.e, I do have the weights on the flaperons, Im sure to do it right would be to switch the wings. I was wondering if a model 4 speedster wings would adapt to model 3 ? Or does anybody have any suggestions on possibly modifing the 3 wings

thanks

chris

[Dave S]

Chris,

Please take this in a friendly way :), we'd prefer you stay in the gene pool......there is a reason it is called VNE :eek: - and, an airframe may have a number of reasons a builder:o of a kit would not be aware of as to why the VNE is where it is on a particular design.

Just a friendly thought.

Sincerely,

Dave

[DesertFox4]

foxkit3, a model 4 wing would give you a much better cruise speed but not much you can do with the model 3 wing to make it faster. With your engine and prop. combo. your are at max speeds already. With the under-camber wing I was told it has flow separation on the underside much above 100 mph. I had your same set up on my first Kitfox, a model 3 with 912/Ivo in-flight ultra-light prop. As you said it can accelerate past VNE no problem in level flight and at the upper speeds trim becomes a real problem with quite a bit of forward stick pressure needed to stay level.

I believe some have adapted a model 4 wing system onto a model 3 fuselage. If memory serves the spar attachment points may the same. The model 4 flight control mixer would need to be installed. You would need heavier struts and you may need to strengthen the bottom carry through. Not many were converted I believe due to the amount of work required to complete the modifications. I thought it easier to sell my 3 unmodified to someone that loves the 3's performance characteristics and build a model 4. My model 3 equipped like yours was a real blast to fly. I put over 900 hours on mine in the first 3 years I owned it. I just had a tough time keeping up with buddies that were all flying model 4's and 5's at the time.

Please use caution when exploring the upper and lower ends of your Kitfox's performance envelope. As Dave stated, be prudent and reasonable when flying your Kitfox. ;)

[foxkit3]

Thanks for the info I appreciate it. Im not looking to kill myself or be care less. Im a safe cautious pilot. I probley should have worded it differently. Would it be possible to raise my v.n.e limit buy adapting model 4 wings to a 3. Just looking for a winter project.