Well Bob, you may no longer be in your working years (though some of your posts I have seen, describing what you stay busy with in your retirement years makes it seem like you still are
), but your phrase still applies...
"I feel certain" does not constitute facts and data.
The reality is, Van's doesn't have a big data base of research done on A model flip-over accidents, and doesn't have any more information about most accidents than anyone else does that spent the time looking at what is available in the NTSB reports.
Occasionally, the NTSB requests assistance, but I think most of those instances have been fatal accidents where having someone very familiar with the engineering, and the structures is helpful.
The FAA has requested help with an RV-12 nose gear failure. As a result, some specific static load testing was done on a sampling of nose gear forks. Based on the data from those tests, the data that was acquired from the EFIS system in the accident airplane, and factored with photos of the touchdown (impact) point
s on a grass runway, they were fully satisfied that the accident was the result of pilot error. As I have already mentioned is most often the case, the pilots account of what happened didn't entirely match up with what all of the other data clear showed happened.
Since the release of the NTSB report you sited (almost 7 years ago now, and Van's contributed data and information to it), I am not aware of them having any interest in having another look at it.
So, in a nut shell, even if I was in a position to provide you with an answer to your questions, I wouldn't have any more data to give credible answers, than anyone else who has spent time researching in the NTSB report (no easy task).
One thing I would like to make clear (and then I am clearing out of this thread)...
I personally own an RV-6A.
I purchased it damaged, as a result of a flip over accident.
The accident was totally pilot error (and listed so in the NTSB final report)
Because of my communications with the original builder / accident pilot, I know some details of the accident that didn't even make it into the report.
So I have my own personal interest in the subject.
I said it once, but I will repeat it again, without some method of data collection outside of the account that the pilot or other witnesses can give, knowing what the actual cause of an accident like this is can be difficult. I am not saying that developing a process to gather data is not worth the effort, just saying that it will be of much less value if something to substantiate the personal account of what happened is not part of the report.
I fully rebuilt the airplane and have been flying it for about 5 years. It is based at an airport with a paved and a grass runway. I probably make 95% of my home base landings on the grass (cheapskate... like to save wear on tires), with the original version nose gear fork <gasp>.
No one at Van's has ever swept this under the rug, as some have been very vocal in proclaiming.
I think the attitude is more along the lines of being realistic (as Alan did a good job of saying earlier). The realistic attitude is that the airplanes are one big engineering compromise... with the goal of attaining the best (ultimate) performance possible.
Could the nose gear be more forgiving. Sure (and since that seems to be a good idea for a lot of the pilot population, the RV-14A was born), at the cost of simplicity and the balance of engineering compromises that exist right now.
As we know, RV's are experimental class airplanes. If an owner decides they don't like the way the different compromises align, they are free to align them a different way.
Comments have been made comparing an RV-6A to a C-150... keep in mind that an average empty weight C-150 (with a stink-en little O-200 on the front) is about the same as a lot of fixed pitch prop RV-6A's.
My personal feelings (as everything in this post is... what I said above is in no way speaking for Van's or anyone else who works there).
If someone has an interest in really getting to the bottom of this, and if they could
objectively look through all of the accidents with enough data available to determine in which accidents it was simply a pilot having a bad day (I say if, because in a lot of them it is not possible), and then would focus on what is left, I believe it would look like a much smaller problem.
Over, and out!