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Archive for January, 2010
Posted by A Useless Geek | Jan 24, 2010 @ 02:30 PM | 6,349 Views
Here's an idea that I've been wanting to try out for some time now. You know how MS Composit makes those sport planes with EPP fuselage and wings but EPS tail feathers? Well, I wanted to try out a medium performance sport plane using the same idea.

There's no reason you have to settle for one particular material to construct an entire airplane. You don't use one type of glue exclusively, do you? Or one type of material for bracing or undercarriage? Well, bunkie, the same thinking applies to the airframe as well.

One of the consistent problems I was having with the SDXS and Smarty Pants Darts was the general weakness of the pink foam fuselage. These planes would crack and break where the servos were installed and where the wing and horiz stab overlapped. Since the original idea was to make these things without a lot of bracing I needed a solution to the breakage that did not include CF or bamboo rods, etc.

The obvious solution is a mostly EPP airframe. If the fuse is tall enough it can flex a little in the vertical axis on minor impact without breaking. The same for the wings. The joint between the wings and top edge of the fuse stiffens the fuse longitudinally and forms a backbone for the plane.

The problem with EPP for the tail feathers is the flex in the control surfaces. Typically fully EPP planes have CF rods in the rudder and elevator to prevent these pieces from flopping around when the plane is under load. I have no objection to doing this, since I've used...Continue Reading