Icon's spin resistant claim and its demonstration video

There was a short thread on this topic in Feb. This is a very nice technology that I personally think should be used in every plane. With the newly released demo video, I would like to see more discussions on it.

The video shows a pretty benign condition for the failed spin entry: idle power, neutral aileron (the pilot keep the stick centered while and after pulling), limited rudder deflection. I would expect the spin resistant claim to base on a much tougher condition: full power, opposite aileron, more rudder deflection.

The video shows the rudder deflection is limited even with the all-the-way-in right leg of the A5 pilot. Does Icon limit the rudder authority at high AoA only, or at all AoA? If the rudder deflection is so limited in all condition, then I would expect it to have poor cross-wind landing capability and poor spin recovery (after all, it is not spin-proof).

Another (perhaps the most) important parameter in spin entry and recovery is C.G. location. The video says nothing about this. In terms of aileron position, FAR 23 clearly states full opposite aileron position is also required.

What are the "tricks" that make an airplane spin resistant? Anyone plans to build an experimental spin resistant airplane at home?

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This is a very nice technology that I personally think should be used in every plane.

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Yeah, that's what has been said since Fred Wieck introduce the Ercoupe back in the 1940s with a much more attractive aircraft that was highly stall resistant and almost spin proof. If you do get into a spin, the aircraft (at least as originally designed) comes out of it even if you try to hold it in a cross control scenario.

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What are the "tricks" that make an airplane spin resistant?

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The fundamental design feature that avoids a spin (or prevents you from being in a sustained one at least) is avoiding at all costs a scenario where one wing is more stalled than the other. This goes right back to Langewiesche. The other way important issue is to have the stall originate at the root (and to a degree that you'll "mush" before the stall reaches the ailerons). The Ercoupe also used the downwash of the wing to somewhat disrupt the airflow over the horizontal stabilizer and elevator which helped to induce a mush before you get to the point of a stall in all but a narrow set of parameters (one example I know of was a guy who tried to prove that you could stall an Ercoupe by doing a dive to Vne and then pulling out into an attempt at a hammerhead stall). I do not recommend either the Vne dive pullout trick or the us of wing downwash by someone who isn't a master of aerodynamics (read as: you, me probably all but one or two folks on this forum).

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Anyone plans to build an experimental spin resistant airplane at home?

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I'm more interested in try to avoid the stall that precedes most fatal spins. Limited elevator authority is one way of doing it. Basically you run out of elevator authority to hold the nose up before the aircraft fully stalls so you just kind of mush downward.

Not an aerodynamicist obviously, but that's what I do know about the subject.