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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Or for getting started on doing them and finding the data at least. When a television station went off the air at night, people saw airfiol on their tv screens.

Fortunately, the step is relatively small in the big scheme of things and the aircraft can aitfoil perform normally. I am perfectly willing to let this one slide if you have the content covered elsewhere, eh? They are less affected by strong winds. They still didn’t have high tech scientific measurements to prove that it could fly Home Questions Tags Users Unanswered.

And, the KF airfoil can also handle a shifting CG and still give you good control authority. For indoor light weight models the extra layer adds unwanted weight. I felt compelled to add this here right up front, so others can not only benefit from it, but maybe it will spark some ideas to apply some science and testing to prove out why the KFm airfoils work as they do.

Please note that the second drawing shows curved airfoils not variations from flat plates. A study by Fathi Finaish and Stephen Witherspoon at the University of Missouri tested numerous step configurations in a wind tunnel. This makes flying wings easier to fly and more maneuverable in higher angles of attack and low speeds.


Jack Images View all Images in thread Views: Reflex, which will produce some drag, means that the ailerons are angled upwards slightly in order to keep the nose of the aircraft pointed up. Archived from the original PDF on A Useless Geek wrote: Spar reinforcementI use either a CF rod or pallet strapping. This thread is privately moderated by jackerbeswho may elect to delete unwanted replies.

KFm-4 airfoil for speed and stability

The thread is not meant just for engineers and scientists. The airfool portion of the airfoil does very little actual lifting. On a conventional airfoil the air must follow the sloping rear section of the airfoil, which at 0 degrees AoA is already at a degree slope away from the airstream.

The basic KF sections all fly well, so I recommend it for all powered sport models. And, now for the most amazing aspect of all I’ve been thinking that we are going to need some aircraft designed for our testing purposes. Air is then eventually pushed to the front of the wing by the airstream that passed over the step.

It reminded me of Burnelli lifting body story and the resistance of the industry to consider anything different. As such, I am always on the lookout for new and innovative ways to build models that are both durable and perform well….

People with the money to do so would rather ignore the KFm rather than testing its merits. I used an OrangeRX receiver to get started as they are just so cheap and so easy to use! It is capable of flying without stabilizers or rudder, which means that two components which cause drag are eliminated. The Airfoils illustrated in this article are examples of those used in radio control foam models. It was then clear to me to improve the flight flexibility of the plane while maintaining if not improving stability and increasing the speed envelope, in theory, would be turning kf, the KFm airfoil.


KFm-4 airfoil for speed and stability | Flite Test

The lfm shows the eight KF variants currently in use or proposed. For an RC foam aircraft, this can be done by simply adding another layer of foam to the top of the existing wing. This meant a lot of lift over the wing was lost. How do KFm step airfoils work?

Other than that I’ve been pretty meticulous. By using this site, you agree to the Terms of Use and Privacy Policy. They make good gliders, but not competitive gliders. It is as good an explanation as we have ever gotten. I’ve been thinking long and hard about the KFm and why it flies the way it does and I may have some answers. Park Pilot is a quarterly publication for the Academy of Model Aeronautics.

It is also well known that flying wings are extremely airffoil and stall easily in flight. Indeed, “vastly different configurations may be needed during a single maneuver.

Sign up now to remove ads between posts. This Kline-Fogleman is my next project. I tested this in the late 40’s and early 50’s. Should we call an airfoil section airdoil of two triangles the Carmel Pule” airfoil? The KF wings are easy to build and inexpensive to make.