I put a bit more faith in them having flown demonstration planes. But obviously not the total package. Remember the USAF and USN have their own known but controlled airspace and airbases Groom lake and China lake where we know more about what people think is going on that what actually is.
As to the computer simulations those are more and more important as they allow development in a faster pace. Boeing’s concept shown above is in a video showcasing how they are trying to transition from the old school design model to a new one that doesn’t just ease development but also has ramifications for maintenance and manufacturing. The “digital” twin means that the fighter built will transition away unexpected design issues by ensuring problems are identified before that happens. By turning repairs into preventive maintenance and easing manufacturing of aircraft as much more of the work can be automated.
Farther as more and more about sixths generation concepts emerge the less we are seeing phasers and photon torpedoes and the more we are seeing missiles and sensors. Less revolutionary more evolutionary. Which is why I put more faith in it. The airframes are not the big deal here.
It’s about the sensors, the defenses, the ability to communicate and integrate. Manned fighters can’t maneuver beyond what they can today without killing the pilots so hyper maneuvering is pointless. Hypersonic fighters have limited utility. so why bother?Extreme altitude is nice, but it’s not actually meant to fight Space aliens…
Stealth have taken the place as why try and knife fight in a phone booth when you can snipe? Node and sensor. Find the other guy first and kill before he realizes he’s in trouble.
Finally The US has the edge in a number of arenas in this category. Not just propulsion. But sensors, systems, low observability. This combination with the changes in manufacturing being looked at means that the U.S. is taking this very seriously.
What this really boils down to is that we are in the middle of a transition. The cloud age had replaced the Information Age and it’s pushing a whole new concept of the industry and design development process. That’s part of sixth generation.
China I have no doubt is deeply interested and concerned about the potential of NGAD & F/Axx though they are not the end all be all of the USAF/USN they will be important assets in the U.S. tool box. However the Ball is in the U.S. court. The Chinese can concept but they are working on major updates to J20, moving J35 from prototypes to practical applications. They are still doing a lot of Cetchup. It seems at this point like GCAP will be flying demonstration before the Chinese.
The Russians on the other hand are in no position to even doodle a sixth generation fighter. They haven’t gotten SU57 into serious production, the few they have are mostly prototypes. Even then the RCS is by the Russians one admission closer to that of a 4.5 Gen fighter. A step up vs the Flanker, Fulcrum or Foxbat but a giant flying billboard compared to the more numerous western counterparts. The SU75 is marketing materials at this point questionable if it will even fly this decade. It’s better than the Iranian farce but still far behind. We haven’t even started yet on the other Russian dreams. PAK DP, PAK DA. Unless Alien Space Bats drop into the Kremlins presidential apartments for a spot of Polonium tea, You will see the French FCAS in production before the Russian.