Another build of my own design.
After a few doodles and working on a wing planform that has been floating around in my head for a while now I came up with this:
I'm sure it's pretty obvious where I got the idea for the wing shape from. Birds of prey and many seabirds (actually most birds) have this shape to their wings. In no way does this imply that anything with this wingshape is going to fly well, in fact through many tests aircraft designers have come to the conclusion that it's more due to the need to be able to get their wings out of the way when they're not flying that birds have evolved into having bent wings. The best fliers out there, like the wandering albatross, have very long straight wings but I have always been taken by the classic bird of prey shape.
So the first step was to build a small throw plane to test the concept. To my great surprise it flew really well. Actually I shouldn't have been surprised, as they say, if you have the right COG and enough power, a toaster will fly. Thankfully my idea wasn't at all toaster shaped so power wasn't too much of an issue!
That evening I got to building and I applied some rules (not for any other reason than aesthetics) derived from photography. Namely the rules of thirds. The rules of thirds suggests that the most effective and attractive photos typically have the image split into thirds either horizontally or vertically (over simplified but this is the gist of it). I decided to leave the rudder for now and went with a bank and yank configuration with two servos on the wings so that I could at a later stage experiment with flaperons.
So I give you - The Kestrel
It flies really well once the CG is sorted and has a surprisingly benign stall characteristic. It will basically pancake from the stall and float all the way down. It flies really well fast or slow and is capable of pretty decent roll rates and loops.
Some specs:
A single sheet of 1000mmx800mm Foam Board
Wingspan: 39.5 inches or 1000mm
Length: 33 inches or 840mm
AUW: 30oz or 850g
Wing airfoil: KFM2
Setup:
Motor - EMAX CF2822
Prop - 9x7 Slowfly
ESC - 18amp Hobbywing Flyfun
Battery - 2200mah 3cell 25C
Servos - 3xTurnigy 9g
Video:
http://www.youtube.com/watch?v=4pO-U8XejT0