Of course I have some opinions here.
I learned clearly in 1990 that it is not how tight your corner is, but the illusion of that. In 1990, VCR's were available and good enough to record stunt flights. That happened at the 1990 Nat's. I thought I had a tight corner, but judges and orher pilots told me that Jimmy did. I was puzzled.
Once home with a copy of those flights I played them over and over tracing the path of both Jimmy's and my plane. It wasn't even close!!!
My plane turned a much tighter radius, BUT Jimmy's looked tighter due to its paint scheme and speed. It flew faster and that made it look tighter also. I have never forgotten that demonstration and used it to fashion my corner presentation. I further worked on the stop of the corner to be as abrupt as the start. That also adds to the illusion.
Does it do a 5 foot radius, not a chance, but neither does anyone else.
While we are giving out the secrets, I will give away the other part of your "discovery" - intentional or not. Of course, it's not exactly a secret, you have been demonstrating it for almost 30 years, and while I can't remember you actually directly discussing it, I have. The time it takes to go from "straight" to "turning" is approaching zero. This is where your "Impact" corner would look dramatically different from Orestes'. If anyone takes a look at the second time through the square 8 in the super-slo-mo above (which is EXCELLENT), after the airplane has slowed down and after he has to start repeating the track, you can see the airplane sliding rapidly to the outsides of the corners, almost looking as if (and perhaps really) being pulled out-side by the lift of the elevator (which hurts the turn). The radius decreases as the corner goes on, so the whole thing is in a "transient" condition.
What I see with my eye, and what I would expect to see with the Impact/40VF is that the turn radius is established very early and then just stays at that radius throughout. It's got to have some curl to the entrance, but it certainly looks like it takes almost no time to get going.
I also suspect that the turn would look "better" on the Discovery-Retro version, and that the "crank-up time" issue is probably a function of the airplane maintaining it's speed, or even accelerating as the corner starts. If it had a Retro and a 6" pitch prop, I would expect that as the airplane starts to maneuver, it would also slow down, keeping it from sliding too far out to the side as the turn starts. It might fly better on electric if they changed the flap/elevator ratio closer to 1:1. That aside notwithstanding...
This is one of the things that got our (David, Ted, and my) attention at the 1988 Golden State meet, and what we started out to try to design in and achieve in flying. When it works, it is *undeniable* that it appears more accurate than any previous approaches. That, and the fact that a lot of other people weren't paying *any* attention or making all sorts of arguments to the contrary, is where the perceived "West Coast Bias" came from, as we learned the lesson by observation, and many still to this day haven't gotten it.
The problem is that in international competition NOW, tight corners score. PERIOD. As has been pointed out, if you can't do tight corners on all the high K maneuvers, you will not score well.
How do we fix this??
It depends on your opinion on what is "broken". I don't necessarily buy the premise that they have it "right" and we are doing it "wrong".
I think the only way is for US judges to start recognizing tighter corners and scoring them accordingly. Yes, one has to decide how to judge a perfectly square loop with soft corners versus the same shape but with tighter corners, and then of course a perfect geometry with tight corners but with a slight hop on one corner.
If this paradigm shift doesn't happen, how will we ever get pilots to fly tight corners and expect to compete at the worlds.
I think you are making some assumptions that I think are quite debatable (because I am going to debate them...). You appear to be assuming that the most important goal of stunt is to win the world championship, and that US judge's and flier's goal is to train themselves for competition in the WC. Also, the implication is emphasis on corner radius is both the sole reason for success, and that this is something we are doing wrong that we should be looking to "fix".
I would dispute all of those points. The current apparent (note: apparent) emphasis on corner radius appears to me to be an overreaction to previous, different overemphasis on other standards, specifically 5 foot bottoms, in the era that you couldn't tell the difference between round 8s and square 8s. At the time, many people in the US argued that this was a distortion of the intent of the rules, which have "5 foot altitude" or some equivalent, and then 10,000 other words. For a while, it appeared that they read the first 3 words and ignored the rest. Well, after not inconsiderable lobbying and discussion, and some other factors I decline to discuss in public, now the apparent (note again: apparent) approach is to look at the "5 foot radius" and not really considering the other aspects.
So, it could be argued that the emphasis has shifted from one narrow view to a different, equally narrow view, both of which are mistakes/not really the intent of the rules.
Note that while it is perfectly clear that the emphasis has shifted and you are certainly well-capable of evaluating what it takes to win stunt contests, in the problem at hand, I would contend that there were quite obviously other factors involved. I will decline to discuss them here, for exactly the same reason from the other thread. I think we even discussed it at the NWR this year. But, for sake of argument, let's grant the premise that the way to win "world" contests is to turn tighter.
That doesn't mean that they have it "more correct" than we do, and that we should "fix" US stunt to do it their way. Even if it *is* the way to be successful at the WC, that doesn't mean the emphasis here should change, if we happen to think we/US are doing it more correctly, with a balanced weighting of all the aspects, instead of homing in and providing emphasis on just one aspect. I think the US Nationals judging corp has been very consistent over several decades in weighting the various factors appropriately.
I removed the 5 foot radius words to attempt to reflect this approach - not to "reduce emphasis" but to reflect the recognition that it is physically impossible for any airplane with conventional aerodynamics. And, additionally, to remove the tendency of a few to home in on what appears to be an engineering requirement and forgetting about the rest of it. Which, interestingly, is also the premise I dispute in the current FAI emphasis.
Turning tighter still gets you better scores in the US, too. It's just that it's not the sole determining factor.
I do not think that we should try to "fix" something in US stunt that we have absolutely no agreement is broken, just to follow the current FAI trend. Nor do I consider US competition as a "AAA Baseball" training league for the WC. I think success in US stunt is at least as legitimate a goal as success in "world" stunt. Now, of course, that might be considered self-serving considering my US success compared to my non-existent "world" success, and I am willing to grant you, Bobby, Billy, David, and Orestes' different perspective, but I bet there are plenty of other people with have *neither* experience that feel the way I do.
We have a few youngsters coming up that still have time to train themselves to do tighter corners. Again, if their tighter corners are not rewarded (as the rules dictate) then they will never develop the muscles and reflexes for future use.
So, if I am all wet, where am I wrong on this?
Igor is not exactly a spring chicken, and he managed to tighten up drastically since the 2004 NATs when I first met him, so people who want to do it generally have a lot of time to prepare. Turning tighter (without losing everything else) will still help them in the USA. It counts for a lot, here, too - just not everything. Which is what I think it should be.
It's not a matter of right and wrong, it's entirely a matter of opinion where the emphasis should lie.
Brett