Above is a mute point
I'd always heard of a "moot point" but maybe on this side of the pond it's different.
@White Ovies:
Agree that as of this writing, XB-47 is still in the 'great potential' category and a work in progress. (I recall how long ago XV-15 was first out and about flying, and how long it took to get V-22 IOC ...)
If we look at the life span of fighters in the jet age, it appears that a good design has about a 30 year life span, with the Phantom being a bit of an outlier in terms of longer. Tomcat went a bit past 30 years. F-18 A/B's are about done, not sure how much longer the C/D's will be in service. E/F's are comparatively new (mid-late 90's, right?)
Let's say F-35 gets IOC in 2016-2017 time frame ... they'll be flying about until 2047-2050.
What does 30 years means in development? F-18 to F-35 is one template to follow.
On a different layer of complexity, rotary wing, the AH-1G showed up as an attack helicopter in 1965/1967, but as it had some commonality with the Huey ... maybe a bad example, but I'll roll with it.
30 years later, 1996, Comanche was flying. The difference in capability and tech was profound.
(Sure, at that point the Mission Systems weren't quite there yet, and sadly, Comanche lost the great budget wars).
Is there a breakthrough pending that makes 6th gen FJ something substantially different from this 5th gen? I've no idea.
We probably don't know fully what "5th gen" does/means for a while in the multi role fighter. It's early yet.
In the meantime, the AI side is just now opening doors they couldn't ten years ago, which suggests to me that projects similar to XB-47 will see faster rates of capability improvement than the move from 5th to 6th gen, or maybe they both join up in 6th gen.
OK, head hurts, off for a cup of coffee.