totoro said:
We don't really know how much smaller, if any, B-21 is going to be. It does seem the requirements and size grew over time, over the last 10 or so years.
Also, size is not really very relevant. Complexity is. Of which we know little, if any.
F-35 was using much more advanced manufacturing than older planes yet that didn't help. So requirements and complexity trump all those.
That being said, I don't see why B-21 could not indeed make the first flight sometime in summer of 2022. Still on track for entry into service in late 2020s.
Complexity is relative.
All the 'tech' in B-21 is supposedly the 'latest' but not "new" for the program. Airframe and integration were to be the 'only' new endeavors. How difficult is building a new airframe? Even though it's a clean-sheet design, it looks a lot like B-2 to me and they've been working on B-2 and it's maintenance upgrades for 30 years. I wouldn't be surprised if there is very little risk here except for manufacturing techniques. And if there is, the risk was mitigated with RQ-180. How successful is the integration? We'll see in testing. Yet modeling flight dynamics was pretty good even back with YF-23 and that was 30 years ago.
F-35 was different, ostensibly one but really three new airframes and net new tech throughout. That's what B-21 program was seeking to avoid from what I understood. Also, F-35 has 1500 domestic and nine partner countries of international suppliers. B-21 has 7 top-tier suppliers and NG supplies significant portions of F-35 tech, some portion of which will be in B-21. It's likely that Palmdale is not only being used for final assembly but that a large amount of process and part work is also being done there. Vertical integration also adds a certain level of efficiency.
DoD was beat up pretty good for B-2 with $20B in R&D cost. It was further beat up by F-35 but those 1500 suppliers in almost every state guaranteed some base level of congressional support. It's likely why B-21 is being handled by the Air Force Rapid Capabilities Office to limit the possibility of bureaucratic changes to the program. Also, the DoD is not allowing cost information to be used politically. Strategically and fiscally the US can't afford another program debacle like F-35.
NG seems risk averse to me. They ate the F-20. YF-23 didn't win, probably in part because of the late USAF changes to B-2 and the difficulties those changes saddled on the program. We've seen them remove themselves from TX and then the X-47B change in priorities. Looking at how they've written the contracts for B-21, they have chosen to protect themselves financially from the changing priorities of DoD. That being said, they are a relatively nimble (compared to Boeing and LM) company focused on engineered solutions. NG's outreach to automobile manufacture assembly line suppliers allowed them to develop the Integrated Assembly Line (IAL) for F-35. The IAL has achieved a 450% increase in throughput cutting the assembly time of all three of the F-35 center fuselage by half compared to previous fighters. This history suggests to me they may have their ducks in a row for the B-21 build.
So now we have the unique situation of DoD recognizing their procurement shortcomings and taking steps to mitigate political and bureaucratic influences and the manufacturer a bit gun shy. We've seen NG partner with KUKA Systems North America early in the B-21 program, the same group that help create the IAL. We seen NG already hire some 5000 employees working B-21 at the Palmdale plant
If I were NG, I'd suspect that the perceived success or difficulty with B-21 and F-35 will play some part in what company is trusted with the next prize, PCA and F/A-XX. For these reasons I expect NG will surprise us with B-21.
