KRnetHeads, At the Gathering, it was brought up that a downside to the "new airfoil" is that the aileron bellcrank has to be modified (due to the thinner airfoil cross section at the bellcrank location, I assume). One look at that bellcrank was enough to tell me that I needed something entirely different, so I did it my own way anyway (well documented at http://www.n56ml.com/owings.html, but not really relevant to my point). To me, the advantages of a wing with less drag, longer range, higher speeds, longer glide distance, and similar stall characteristics out-weigh the advantage of "just follow the plans" when it comes to the bellcrank.
A lot of folks have opted for the new airfoil and managed to alter the bellcrank to work successfully, so would those that have, please post a link as to how they did it? This should remove any issue with building the new wing, for those who are concerned. My guess is that the result was simpler and more elegant than the bellcrank shown in the plans. The old newsletters show several ways to improve on the old bellcrank, so I'm not the first guy to think it was a bit convoluted. Also mentioned at the gathering was that there was no real discussion of the differences between the three versions of the airfoil, so I edited that to point out the it's all about thickness-to-chord length ratio. See http://www.krnet.org/as504x (near the bottom) for that, and even more at http://www.krnet.org/as504x/templates.html . I think it's pretty safe to say that if you are building a new KR2 or KR2S, you should be using the new airfoil. Templates are free and located at the bottom of the previous link. With many years of "testing" by lots of KR pilots, it is well proven at this point. -- Mark Langford ML at N56ML.com http://www.n56ml.com
