The Rasberry is an interesting concept and from the bit of curiosity analysis I did several years back, it actually stood a good chance of success. Contrary to what the short blurb next to it indicates, the landing speed might have been crisp, but not excessively so. The highly straked body actually creates a significant amount of lift and as such, the actual planform loading is quite low. Furthermore, the wing stubs act sort of like winglets in that they provide the airplane with behavior that seems to be more efficient than you'd have with such a low aspect ratio planform. Coupled with the potential for making use of vortex lift, this could've been quite fun and not a bad handling airframe.

The comment regarding the engine placement however does have merit. Given the short coupled nature of this small design, the high placement of the prop would most likely have had some interesting pitch trim characteristics as a function of throttle. Ideally the prop should be much lower, which would then of course affect things like prop selection and of course landing gear design.

The issue I was most concerned with however was the pitch chracteristics as a function of aoa. The behavior of the body strake would have to be very carefully tailored for predictable vortex formation. Most likely it would need a fairly generous LE radius in order for the flow to stay attached to fairly high angles of attack since an early separation would form the vortex and thus shift the Cp a bit too dramatically for linear control. This aspect would require significant testing and optimization.

Looks like fun though.

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