Hello,
I am pleased to receive many constructive thoughts and comments about hinge-to-hinge distance and flaps geometry (ref:
https://stunthanger.com/smf/open-forum/hinge-to-hinge-distance and
https://stunthanger.com/smf/open-forum/flaps-geometry/ ).
After my latest conversation with Igor Burger (ref:https://stunthanger.com/smf/open-forum/flaps-geometry/ ), I started thinking about relationship between the RTF model C.G position and the shape of the wing and the horizontal tail assembly airfoils. Specifically, I wanted to understand the aerodynamic differences between "classic modern stunt" design and Igor's Max Bee II.
Like I wrote in
https://stunthanger.com/smf/open-forum/flaps-geometry/, my Big Red is based on Igor's Max Bee II but still requires certain modifications in order to improve turning in sharp corners.
Please see the attached: this sketch shows two configurations: "A" - that I am proposing to call "classic modern stunt" and "B" - Max Bee II type designs.
The lift diagrams (ref: JavaFoil computations) show that the stunt models having configuration "A" must have the RTF C.G
MORE FORWARD than the models having configuration "B", in order to achieve better turning agility.
Please note that the hinge-to-hinge (h-t-h) distance, chords of the lift generating shapes and the sweep angle of the L.E are the same for both configurations but the maximum lift X coordinates are different.
Comment 1: X axis of the Cartesian Coordinate System is along the airfoils chords.
Comment 2: Max Bee II wings airfoil shape is a derivative of Van de Vooren, Helmbold-Keune and/or Rosner shapes (ref: JavaFoil Users Guide.pdf). Max Bee II horizontal stabilizer airfoil has the unique shape too.
I welcome your comments and constructive criticism, as long as associated with valid and well justified suggestions and ideas.
Stay Safe and Fly Safe (soon..?),
Best Regards,
M
Topic: C.G position, hinge-to-hinge distance, airfoils and more (Read 820 times)