Welcome to the ** Kline-Fogleman (KFm) Airfoils – Advanced Theory/Science ** discussion thread. The purpose of this thread is to try and. The simplicity and performance of the KF airfoil have made it popular in the Maker Trainer 2 and uses the KFm-2 (Kline-Fogelman model 2) airfoil design (a. The idea works but only with active automated re-configuration of the shape of the step(s) during flight. Further testing has shown that this airfoil.
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A great example of this technique used is found on the versa wing. Nicholas 5 8.
KFm wings a basic explanation
After reviewing his work I decided to build the MF Hornet. Should motivate some real interest When forced into a stall which is hard to dothe Maker Trainer 2 tips slightly forward and regains speed. The original Klein-Foggleman patent was for an aairfoil with the step on the bottom of the wing.
Unfortunately, there were some complications when filing and writing the patent.
High winds seem to have little effect on how it performs. FreeMan 6, 6 54 The KF wings are superb on all sport powered modelsthey are not so good on some of the other model types. Sign up now to remove ads between posts.
Poor lift-to-drag ratio performance in wind tunnel testing has meant that to date the KF airfoil has not been used on any full size aircraft. As Dave from RCsuperpowers stated “their is some magic that you dont find in the other wings” that happens and is immediately felt at any speed. I think that is what this thread is about to try and do. The attached study, published by Rich Thompson in Februaryis arguably the best comparison study of KFm airfoils that has been accomplished to date.
If the KF airfoil is new to you and you’re interested in a little of the history of it, this wiki page has a good summary of all the details: They are very responsive with excellent control authority. KFm wings a basic explanation. The fight characteristics, however we greatly enhanced. Email Required, but never shown.
We need to build multiple models that vary in only one area such as size, shape, or type of KF variant at alrfoil time. The plane was faster, more stable, and the speed envelope was increased. Reaction to the KF airfoils is usually disbelief at first. You need to log-in to comment on articles.
KFm wings a basic explanation | Flite Test
I remember taking the plane and had to travel on a bus. I’d love to see something like that done again today but with wind tunnel data lift, drag, etc. Images View all Images in thread Views: They use plenty of lift for self righting. Although I had no intention of making this an FPV model from the outset I did retain a space in the nose for the GoPro as I knew kfk experience that it was good for balance and also the in-flight footage might be fun!
OKhere ya’ go!!! Thus, a given airfoil can akrfoil certain things well, but do poorly in other areas. Enhancing the aerodynamic performance of stepped airfoils Numerical and Experimental Study 1. Also, I did not want to have to compensate with down elevator when doing a highspeed pass. It was from the big bang, the beginning of the universe. However I do feel that a KF will work as an alternative build.
It is an important work! This captured vortex allows the air to travel almost frictionless over a portion of the wing, decreasing drag, which in turn increases efficiency.
Air must travel faster over the upper surface of an airfoil in order to lower air pressure and thus produce greater air pressure underneath. A step near a hinge line doesn’t give any benefit, with the top step KF builds it appears to cause more problems as any vortex produced ends up on the top of the moving control surface.
It has been noted that during a steep climb, once the throttle is cut back the plane will just settle down and fly level with the ground.
You need to log-in to rate articles. Out comes the glue gun — or does it? I am very familiar with Tony65x55’s designs. And if you can’t The KF family of airfoils are nothing new. A paper airplane that resisted stalling. This is only day one.
Rich Thompson Comparison Study – Feb Files View all Files in thread. It becomes attached to the surface of the airfoil and since is it rotating faster than the air beneath the airfoil, it reduces the air pressure on the upper surface. In one case, 4.