Below is an email & PDF's Dick Kline sent us back in 2009.
Hi Frank and Paul...
I have just written this piece as to why I think the KFm3 airfoil is a heavy lifter. I would like you comments on it. And, please let me know if you disagree with it. Or not. There has never been any official explanation as to why the KFm airfoils work in the first place. Only conjecture.
So here it is, and if you feel you want to post it, go ahead. But only if you think it is spot on.
Hope all is going well for you guys.