Northrop Grumman B-21 Raider (LRS-B)

[Rhinocrates]

Considering how ruthless they've been in shaping the plane, I think it unlikely that there'd be any odd bumps on the final design. Perhaps test equipment or an antenna peculiar to the prototype?

 

[Scott Kenny]

Considering how ruthless they've been in shaping the plane, I think it unlikely that there'd be any odd bumps on the final design. Perhaps test equipment or an antenna peculiar to the prototype?

The light doesn't lie, however. There's a well-faired bump on the tail.

 

[Josh_TN]

The light doesn't lie, however. There's a well-faired bump on the tail.

It might be a test article, but also that would be an incredibly obscure place to generate a radar reflection, especially at 50,000 feet.

 

[4decaa]

Scott is right, that light don't lie!
Considering B-21 test articles are essentially production aircraft, I don't know why there would be anything different on the test aircraft in terms of physical structure. Other than the air probe(s).

There is something (on the back of the aircraft) that the engineering team needed to accommodate for, and this something was worth a rear-aspect RCS penalty.

 

[Training_Dummy]

Closing in on a decade since the announcement of the award. Hoping F-47 does better.

 

[Scott Kenny]

There is something (on the back of the aircraft) that the engineering team needed to accommodate for, and this something was worth a rear-aspect RCS penalty.

I'm leaning towards SATCOM antenna bump, personally. This would shield the antenna from the entire frontal aspect even while the Raider is at 35-40kft, and still let the antenna see the whole sky.

 

[Josh_TN]

Closing in on a decade since the announcement of the award. Hoping F-47 does better.

Not bad for a stealth bomber. It is in LRIP.

I doubt F-47 will do much better.

 

[bring_it_on]

Closing in on a decade since the announcement of the award. Hoping F-47 does better.

They are flying weekly, and are getting ready to dramatically expand the flight test program. Two LRIP contracts awarded (being executed) and another two in long lead procurement. I think the program has done rather well given the initial delay due to protest, a pandemic that disrupted supply chains and workforce and a whole host of other considerations (to include that developing and producing a stealth bomber is not exactly a cakewalk). Most importantly, they are within the schedule (and cost) margins put forward by the AF RCO. That's quite impressive all things considered.

NGAD is intended to do a lot better than this. For starters, the time to first flight is expected to take half as long as that on B-21. Low Rate production likewise will probably begin at least a couple of years to the left of when it happened on the B-21. If not even sooner. I would not rule out an LRIP award (or two) before the end of the decade for deliveries to first units beginning in the early 2030s (I expect at least one LRIP award in the 2028-2030 timeframe for 2032 delivery).

 

[Training_Dummy]

thanks for the counterpoints. I guess more than anything I thought Raiders reliance on high TRL subsystems and NGs experience with the planform might have resulted in even faster progress, but that’s probably the anxiety that comes with seeing half of the deployable B-2 fleet making holes in a desert half a world away and realizing Raider can’t come soon enough. In the end, the government seems to be working with NG to accelerate and potentially increase deliveries.

 

[Josh_TN]

thanks for the counterpoints. I guess more than anything I thought Raiders reliance on high TRL subsystems and NGs experience with the planform might have resulted in even faster progress, but that’s probably the anxiety that comes with seeing half of the deployable B-2 fleet making holes in a desert half a world away and realizing Raider can’t come soon enough. In the end, the government seems to be working with NG to accelerate and potentially increase deliveries.

The B-21 benefited from being run by the RCO with a stipulation that all items inside it were at TRL-6 or above. Basically, it had to be more or less a demonstrated technology to be considered. Luckily, the U.S. has a lot of tech just on the shelf, relative to it’s competitors.

 

[Training_Dummy]

Was just also doing a bit of legwork - starting from the first a/c, Raider was supposed to fly with installed mission systems, as opposed to pumping out a few test articles with core flight systems only and weights to simulate the rest, just to fill out the test flight envelope as quickly as possible. Non-trivial factor.

 

[bring_it_on]

The B-21 benefited from being run by the RCO with a stipulation that all items inside it were at TRL-6 or above.

That's not a RCO thing. That's an actual requirement for a MDAP entering EMD. I believe this was set in place in the mid 2000s and further reinforced in 2012. These would have been the criteria regardless of which program office managed the LRS-B.

“TRL 6 (required for approval at Milestone B), must be demonstrated (hardware) or validated (software) in a relevant environment.

https://www.cto.mil/wp-content/uploads/2023/07/TRA-Guide-Jun2023.pdf

The National Defense Authorization Act (NDAA) of 2006 established statutory law for the Milestone Decision Authority to certify that all critical technologies (i.e., referred to as critical technology elements) have been demonstrated in a relevant environment (i.e., TRL 6) before granting an MDAP approval to enter EMD (NDAA, 2006). With the advent of key legislation and resulting DoD acquisition reform initiatives, weapon systems programs are now required to enforce a technology development strategy that can foster true risk reduction prior to entering systems development.

US DOD Technology Readiness Assessment (TRA) based risk assessment methodology stress on System Prototype Demonstrations in Major Defense Acquisition Programs - International Defense Security & Technology

Federal agencies spend billions of dollars each year to develop, acquire, and build major systems, f

idstch.com

I believe the B-21 benefited a lot from RCO's tight control of requirements, and the authority to change requirements residing at a very high level and the resultant benefits of requirements stability. Digital capabilites also contributed leading to a very mature and stable first aircraft configuration and mission system incorporation. NGAD will be head of B-21 even in these areas..

Slightly off topic but the DOD IG had some questions regarding NGAD's TRA and whether it was even ready to push through into EMD in FY24/25. They backed off once Kendall put it on ice and have been quite since but clearly that's still a requirement for it to enter that phase of the program as it is the law.

 

[Josh_TN]

Ok, fair correction, but broadly I think my post was not inaccurate: the LRSO program that became the the B-21 benefited from an RCO development that specifically required a high level of technical maturity for anything going into the aircraft. That is in stark contrast to the NGB project that predated it. And not for nothing, in stark contrast to H-20 or PAK-DA, which for both countries would be massively ground breaking aircraft development.

 

[bring_it_on]

Ok, fair correction, but broadly I think my post was not inaccurate: the LRSO program that became the the B-21 benefited from an RCO development that specifically required a high level of technical maturity for anything going into the aircraft. That is in stark contrast to the NGB project that predated it. And not for nothing, in stark contrast to H-20 or PAK-DA, which for both countries would be massively ground breaking aircraft development.

Yes largely correct. They added 5-10 years to the schedule and reduced requirements and technology on the LRS-B as they transitioned from NGB. The added time, and lower technology and size meant a less capable but a lot more affordable aircraft.

 

[NMaude]

The added time, and lower technology and size meant a less capable but a lot more affordable aircraft.

Basically getting an aircraft good enough for the and at a price that won't break the bank enabling large numbers to be built.

 

[In_A_Dream]

With the upgrades being made to the B-21 line at Palmdale, any guesses on the production rate once it completes LRIP?