The knowledge component would include the necessary manufacturing expertise for the numerous specialized parts required by a modern fighter design. Canada had all these assets in the late 1950s but ran short on the last component, political will. ICBMs largely negated the need for a dedicated interceptor for confronting Soviet bombers so the Arrow wasn't needed. Rather than redirect to program towards a multi-role fighter, the government of the day destroyed the country's military aviation industry, millions of dollars and effort were all for not. Contrast this story with Australia's Collins program, 8 very capable subs with the industrial infrastructure still in place to work on a replacement. There was political waffling but fortunately not enough to be fatal to the program.
I literally cannot emphasise enough how much programs like this can be worth in this respect. You need to understand what you know and, just as crucially, what you don't.
If that isn't coherent throughout the process you get a differential between concept designers and the unlucky buggers who have to actually figure out a practical solution to stated requirements which have been theoretically solved by a designers belief a particular technology or material exists when it doesn't.
Throughout the testing phase of this aircraft, the Japanese aero industry will be gaining a significant amount of understanding about materials, systems integration, advanced manufacturing and all the sub-divisions of those and how they all work together.
It'll be interesting to see how Japan goes in the ITAR route, as a key US ally in the Pacific you'd think it wouldn't be as big of an issue. However France and, increasingly, the UK has in some areas trying to keep ITAR at arms length as much as possible for commercial reasons. I'd like to see if anything from the Japanese program is exportable.
