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Bob Brocious
09-05-2023, 08:07 AM
Hello folks. I purchased my 2nd Kitfox IV from a great aviation family in Canada and trailered it home to Kentucky. I'm going through all the US registration milestones, secured a new US N Number (125PT) and have started taxi tests with several crow hops down the runway.
Sitting in the hangar, moving the flaperons appears to produce some asymmetric behavior that makes me do a double take. I don't need to use them for first flights but ... of course I will soon enough. I plan to check the builder's manual to confirm pushrod length and adjustments. The plane was flying a good bit prior to my purchase. I can't imagine them getting out of adjustment on a trailer even though we drove 1,200 miles.
I thought I saw on some other posts that the flaperons require a flying wing to work as designed and that the behavior I'm seeing may be normal in no-wind situations. I would appreciate any thoughts.
Campbellsburg, Kentucky
Madison, Indiana airport (KIMS)
Bob Brocious
32919

atosrider
09-12-2023, 03:07 AM
Kitfox changed the control linkage design with the "new" model IV wing, so a first check with the builders manual is that it matches the pieces in the plane ..
my unit is a model III with IV wings, so the kit came with, or there was an option to get, a different mixer arrangement, my build manual has hand writing 'not installed' ..
compared to another model IV here, the linkages are a different design, but we didn't fully study any difference in actuation ....

those linkages better not change from trailering ... or with any change in wind speed

avidflyer
09-12-2023, 06:14 AM
Here is a quote from Wikipedia about the Kitfox 4, notice the "differential aileron control system". That means the flaperons do not go up and down the same amount, and that helps to offset adverse yaw. Is this what you are asking about in your question? JImChuk

The Kitfox Model 4 was a new design introduced in 1991. It incorporated a laminar flow (https://en.wikipedia.org/wiki/Laminar_flow) airfoil (https://en.wikipedia.org/wiki/Airfoil), new flaperon design, metal flaperon attach brackets and a new 2:1 differential aileron control system. The gross weight of the Kitfox Model 4-1050 was the same as the Model 3, 1,050 lb (476 kg). The Model 4 standard engines include the 80 hp (60 kW) Rotax 912 and the 100 hp (75 kW) Rotax 912S (https://en.wikipedia.org/wiki/Rotax_912). 322 were built.[10] (https://en.wikipedia.org/wiki/Denney_Kitfox#cite_note-Kitfox4-10)