You can use Twitter with the hash tag #ICanHazPDF2. You cannot. This is why most scientists spend 10 years in University.3. Not at all likely.----------Doing outstanding research must be in Labs ?......
Best bet is to join a masters or doctoral program at a university; however - if you're just hoping to 'discover' something without an idea of what it is.... they are going to consider that a very long shot in the dark...
You cannot have access to classified documents without proper clearance. If you are mistaking "clearance" for "pay walls," then refer to my answer below (1.).
1. You Pay, find a library that carries the journal, or you request a PDF from your scientist friend that has paid. You can use Twitter with the hash tag #ICanHazPDF
2. You cannot. This is why most scientists spend 10 years in University.
3. Not at all likely.
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"Doing outstanding research must be in Labs ? No Numrical or Computer simulation ability ?"
No original research is only done with computers. Where do you suggest you get original data without instruments?
The supposition that the top grade in any research is always classified is probably out of date. Yes, there are many things that are classified, but as soon as they appear in some sort of device that is actually used then they can be reverse engineered if the resources are available. That goes for both software and hardware. If something is possible to one group, then another group will find out ways to do the same thing. The way they do it might be different, but there are many ways of killing a cat.
Several years ago I became aware that a group in our industry and well out of our region were using software that produced a certain result. They refused to sell us a copy for some reason even though were not competitors. So between about three of us we managed to produce a program which produced the same result. We had to work out how it might be done. This took about three weeks of part time effort for non-professional programmers and used first year college mathematics. it probably was not all that difficult, but it illustrates that if you know what the result is and the input, then what goes on in between can probably be worked out.
EDIT Your further details are about computational fluid mechanics. Not a field I'm familiar with but I did learn about Reynolds Numbers etc many years ago. I'm also aware of finite element analysis but I know nothing of it. Can one be applied to another? I don't know but maybe. I suspect the difference between calculating fluid flows etc with a slide rule and with a computer is the difference between the number of things that can be taken into account and the speed of calculation. I see a lot of patents, though not in anything like your field. There is very little difference between one set of patent claims and another.
Things like iPads etc are using techniques and hardware which are probably vastly ahead of what was available to the aerospace sector even ten years ago.