Northrop Grumman B-21 Raider (LRS-B)

CiTrus90 said:
Q-nimbus said:
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Reverse image search on Google...
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http://www.richard-seaman.com/Aircraft/AirShows/Frederick2000/B2/Closeup/index.html
The second one, I'm 95% sure it's just photoshopped as well due to the amount of "grain" and artifacts.
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I think it's a fuzzed PS of the B-2 flights to Korea with an F-16 flying chase. Something from the same flight as the picture here.

https://www.reuters.com/article/us-korea-north-stealth-idUSBRE92R0DX20130328
 
I’m glad that’s sorted out. Of course, in this day and age, if something exotic is flying out there, even the most basic phones should make really sharp and clean pictures.

Apart from the pictures, do you guys think a demonstrator for the B21 was flown?
 
Q-nimbus said:
I’m glad that’s sorted out. Of course, in this day and age, if something exotic is flying out there, even the most basic phones should make really sharp and clean pictures.

Apart from the pictures, do you guys think a demonstrator for the B21 was flown?
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Demonstrator for B-21 was the B-2...
 
Q-nimbus said:
do you guys think a demonstrator for the B21 was flown?
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Sure. Probably more than one.

The things that needed demonstrating weren't dependent on a B-21 shape. They would be demonstrating systems, not the airframe.
 
CBO just released a report that estimated that the marginal cost (in FY20 $) for
a B-21 and 10 LRSOs is $500 million of which two LRSOs would be spares i.e.
the B-21 can carry 8 LRSOs. The carriage capacity is a guess on their part.


...or they say 8 x B61s. Which makes no sense.
So ignore them on payload but the pricing info is interesting.

https://www.cbo.gov/system/files/2020-08/56475-START.pdf
 

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Bhurki said:
marauder2048 said:
the B-21 can carry 8 LRSOs
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So, a single AF rotary launcher?
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To be clear, this is totally a was by the authors.

For this analysis, CBO’s estimates of next-generation forces
incorporate the assumption that the B-21 bomber could carry
up to eight nuclear weapons, half the number that the B-2A
can carry. The actual number and types of nuclear weapons
the B-21 will carry have not been publicly disclosed. For a
public analysis of the potential capabilities of the B-21, see
David Cenciotti and Tom Denerly, “Let’s Have a Look at
the New B-21 ‘Raider’ Stealth Bomber Renderings the Air
Force Has Just Released,” The Aviationist (January 31, 2020),
https://tinyurl.com/ya6kvudz.
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flateric said:
Northrop didn't have to build a demonstrator for B-2 40 years ago, why should it build it now, taking into account giant leap CFD and other things made since then?
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FWIW: since some years have passed - some years ago on FB a definite former Base Worker (by his associations and comments) made a comment in a private group (now removed - so I'm paraphrasing) along the lines of having been amused to see the Televised rollout of the B-2 since Northrop had been flying 'the same basic shape' out at the Ranch 'for years'.

Base workers apparently nicknamed the little Test Vehicle 'The Guppy' because of its ungainly appearance.

This was not TACIT BLUE.
 
Mr London 24/7 said:
flateric said:
Northrop didn't have to build a demonstrator for B-2 40 years ago, why should it build it now, taking into account giant leap CFD and other things made since then?
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FWIW: since some years have passed - some years ago on FB a definite former Base Worker (by his associations and comments) made a comment in a private group (now removed - so I'm paraphrasing) along the lines of having been amused to see the Televised rollout of the B-2 since Northrop had been flying 'the same basic shape' out at the Ranch 'for years'.

Base workers apparently nicknamed the little Test Vehicle 'The Guppy' because of its ungainly appearance.

This was not TACIT BLUE.
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Something appeared in an episode of Unsolved Mysteries back in the 80s as a grainy video that was definitely not a F117 or Tacit Blue. It would be silly to assume the US with a long history or black aircraft stopped at the 117. Obviously as an engineer Northrop didn't hit a home run with the B2 without some subscale tests. You don't build a billion dollar bomber with a revolutionary shape and pray it works out. Computers in the late70s were not up to the task. Lockheed who relied on computers could only design flat plates... There was a guy on ATS named boomer137 with some credible posts.
 
There are probably countless demonstrators/test A/C out at Groom, and when they're full up, they just bury them out back.
 
rooster said:
It would be silly to assume the US with a long history or black aircraft stopped at the 117.
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I do not think that anyone on this forum asserts that the United States - wether that means the Air Force or private companies - stopped conducting classified aircraft programs with SENIOR TREND. After all, TACIT BLUE, Bird of Prey, TEAL DAWN, RQ-170, and others came after SENIOR TREND.

There have also been quite a few that we are now pretty sure didn't exist. Like the "TR-3", which is well documented on their forum.

rooster said:
Obviously as an engineer Northrop didn't hit a home run with the B2 without some subscale tests. You don't build a billion dollar bomber with a revolutionary shape and pray it works out.
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Do when you say "as an engineer Northrop" do you mean Jack Northrop? He had nothing to do with the design of the B-2.
What about the shape of the B-2 was revolutionary?
The B-2 designs were tested extensively in wind tunnels, both private and government owned. Same for RCS ranges. There was not much of a reason to fly "sub scale tests".

rooster said:
Computers in the late70s were not up to the task. Lockheed who relied on computers could only design flat plates... There was a guy on ATS named boomer137 with some credible posts.
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Both Lockheed and Northrop used computers extensively - but not exclusively. Northrop had RCS prediction software much earlier than Lockheed did. Northrop's software was very good at predicting the RCS at lower frequencies. Lockheed's methods were better for higher frequencies. Each company used their software - and other methods - for the XST program. The specific requirements of the XST program favored higher frequencies (and thus Lockheed's methods). Northrop's XST, while very good at a wide range of frequencies, was not as good as Lockheed's at the frequencies in the requirements.

The B-21 is the result of many, many years of risk reduction under many different programs. NGB, LRS-B, etc. That risk reduction did result in demonstrators - ACCA, CalSpan automated refueling tests, and others.
 
TACIT BLUE was the demonstrator for Northrop's RCS reduction techniques much like HAVE BLUE was for Lockheed.

Its possible there were as-yet-undisclosed unmanned subscale flying wing demonstrators for B-2, but what would be the motive for continuing to conceal them?

For B-21, it seems highly unlikely the aerodynamics were the thing needing demonstration.
 
overscan (PaulMM) said:
TACIT BLUE was the demonstrator for Northrop's RCS reduction techniques much like HAVE BLUE was for Lockheed.

Its possible there were as-yet-undisclosed unmanned subscale flying wing demonstrators for B-2, but what would be the motive for continuing to conceal them?

For B-21, it seems highly unlikely the aerodynamics were the thing needing demonstration.
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Scaled Composites Model 401 ?
 

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On a related note; in motorsport, parts are typically designed, tested in a CFD environment, then at [usually] 50% scale and again at 100%. At each stage, modifications have to be made as CFD, whilst useful is not a panacea. One of the 'holy grails' of motorsport aerodynamic is correlation.

All of which is a long-winded way of saying that I'd be astounded if there wasn't some flying hardware to support the programme.
 
The shape of the B-21 is pretty well known and understood aerodynamically and RCS wise. It appears to be exactly what the B-2 was going to be until the low level requirement forced a change. It looks like that engine inlets are recessed, which is a little new, but I suspect computer modeling is sufficiently advanced that they would know if that arrangement is a show stopper or not with physical flying models. Were there every F-22 or F-35 scale models? I remember a lot of surrogate aircraft for the avionics but other than that I think it was pre-production/LRI prod aircraft.
 
If there needs to be a demonstrator it likely to be for things such as aeroelastic control tech that
were looked at but didn't make the cut for B-2 e.g. deformable surfaces.

And the demonstrator probably wouldn't look like a flying wing.

On a related note, the lead guy for the B-2 aeroelastic effort, R.T. Britt, is back, starting 2017,
as a consulting engineer for Northrop Grumman: Melbourne, Florida.
 
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GeorgeA said:
From “Take That, Goliath” by Bill Sweetman, AW&ST, Nov. 9-22, 2015, p28-29:

Some of the key technologies in the LRS-B are both secret and mature. “Not only have some technologies been wind-tunnel-tested, prototypes, or flown – some of them have been used operationally,” [Air Force acquisition chief William] LaPlante said during the Oct. 21 briefing.
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Not only did Boeing and Lockheed Martin outgun their rival fiscally, but they were also teamed on a government-funded demonstrator aircraft, identified as the Next-Generation Long-Range Strike Demonstrator, under an effort that started in the early days of NGB and continued after the ambitious bomber was canceled. The stealth technology group within Boeing’s Phantom Works, headed by Alan Wiechman, led the low-observables side of the program, although Lockheed Martin’s Skunk Works built the airframe.
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There's no hint of it anywhere in the GAO protest; you would fully expect Boeing and Lockheed to
invoke it as evidence of their goodness, righteousness and probity.
 
TomcatViP said:
Would not that be active flutter mitigation?
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From Britt et al.

The Twist Adaptive Wing System (TAWS) and Continuous Aerodynamic Control Surface concepts strive for aerodynamic
controls which are seamless for both improved aerodynamic performance and survivability. TAWS is geared towards
medium to high aspect ratio wings. It incorporates an internal mechanism to twist the wing to provide incremental lift for
maneuvering, load alleviation and performance optimization. The TAWS concept has also showed significant
potential in reduced manufacturing costs by reduced part count and sealing the structure from environmental damage.
Continuous aerodynamic control surfaces technologies can be generally describes as advanced seals
which maintain structural continuity for relatively conventional aerodynamic control mechanisms.

Concepts in this class will be of continued interest for military bombers and transports due to multiple benefits
provided, particularly survivability. In fact, deformable surfaces were considered in the early B-2 design stages,
but were abandoned due to lack of technical readiness and inadequate control authority at low speed.
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The aerolastic component could well be the wing twisting as it bends - as the wing flexes up, washout is introduced that it unloads and bends back down. How that plays into lift distribution (and therefore the stability of a tailless platform) and RCS, well that would be 'parcel of work' alright....

Getting rid of traditional control surfaces (or at least not having to use them in certain scenarios) would be useful too but I'd be surprised if wing warping per se could be used on such a platform. SB4 style wing tips? The joint would provide a challenge or two.

Edit - just seen post by marauder2048
 
No flying demonstrator in 2015 at least.

https://www.flightglobal.com/new-de...as-contract-announcement-nears/118096.article

This week, the service briefed no fewer than 12 Washington defence analysts about the bomber, and the main message was that the technologies being baked into the bomber are more mature and ready than previously disclosed.

There is no flying demonstrator, it has been confirmed, but plenty of prototyping activities and wind tunnel tests have been done, as well as parallel efforts to ready critical subsystems.

Sources who attended the briefing say the optionally-manned, penetrating bomber will be a collection of very mature technologies powered by an advanced derivative of an existing engine.
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GeorgeA said:
marauder2048 said:
There's no hint of it anywhere in the GAO protest; you would fully expect Boeing and Lockheed to invoke it as evidence of their goodness, righteousness and probity.
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Wouldn’t a discussion of a classified vehicle be limited to the classified annex to the protest?
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I am sure Lockheed and Boeing planned to build a demonstrator for NGB. Doubt it got to flying stage though.

That has no bearing on whether Northrop built a demonstrator for B-21.
 
GeorgeA said:
marauder2048 said:
There's no hint of it anywhere in the GAO protest; you would fully expect Boeing and Lockheed to invoke it as evidence of their goodness, righteousness and probity.
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Wouldn’t a discussion of a classified vehicle be limited to the classified annex to the protest?
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The specific reference would be blacked out. But it would look like: "Boeing leveraged work on <blank> to justify
its cost estimate of <blank>." GAO and the AF are explicit in the record in the protest as regarding Boeing's previous work
cited as a basis for estimating cost/risk as having little bearing on LRS-B.
 
It will be interesting to see what sort of design Boeing and Lockheed came up with during the course of the LRS-B programme, I would be highly surprised if they came up with another flying wing design.
 
overscan (PaulMM) said:
GeorgeA said:
marauder2048 said:
There's no hint of it anywhere in the GAO protest; you would fully expect Boeing and Lockheed to invoke it as evidence of their goodness, righteousness and probity.
Click to expand...

Wouldn’t a discussion of a classified vehicle be limited to the classified annex to the protest?
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I am sure Lockheed and Boeing planned to build a demonstrator for NGB. Doubt it got to flying stage though.

That has no bearing on whether Northrop built a demonstrator for B-21.
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Actually, a demonstrator for NGB would have made complete sense: it was supposed to be a VLO bomber
with supersonic dash and (according to former CSAF Norton Schwartz) air-to-air missiles.

The apparent radical descoping for LRS-B would have made flying the NGB demonstrator for it the
crude equivalent of McAir flying the YF-23 for the Super Bug.
 
You don't need a demonstrator if there were/ are other things flying close in mold line to the bomber... In automotive we use surrogate data all the time. Cheaper and faster. So yes, there was no demonstrator and they had surrogate data in hand. $0.02.
 
General Weatherington says, " The onset of ramp may be a bit late, but the ramp will certainly be steeper than initially thought".

Combined with the reduced requirement of combat coded B-1B to 24 (total 45) from 36 (total 62), the B21 certainly has the impetus to not lose a day in being operationalized.
IOC is set for 2030.
 
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It doesn't really matter if you are Biased towards this or that.
The reality is, there will always be Delays on these programs. Change of design, change of requirements perhaps while they are developing it..
The list goes on.
 
Bhurki said:
General Weatherington says, " The onset of ramp may be a bit late, but the ramp will certainly be steeper than initially thought".

Combined with the reduced requirement of combat coded B-1B to 24 (total 45) from 36 (total 62), the B21 certainly has the impetus to not lose a day in being operationalized.
IOC is set for 2030.
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Where do you get a 2030 date for IOC? Do you mean nuclear certified?
 
marauder2048 said:
Bhurki said:
General Weatherington says, " The onset of ramp may be a bit late, but the ramp will certainly be steeper than initially thought".

Combined with the reduced requirement of combat coded B-1B to 24 (total 45) from 36 (total 62), the B21 certainly has the impetus to not lose a day in being operationalized.
IOC is set for 2030.
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Where do you get a 2030 date for IOC? Do you mean nuclear certified?
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General's answer to a question asked in the mitchell inst interview.
 
Bhurki said:
marauder2048 said:
Bhurki said:
General Weatherington says, " The onset of ramp may be a bit late, but the ramp will certainly be steeper than initially thought".

Combined with the reduced requirement of combat coded B-1B to 24 (total 45) from 36 (total 62), the B21 certainly has the impetus to not lose a day in being operationalized.
IOC is set for 2030.
Click to expand...

Where do you get a 2030 date for IOC? Do you mean nuclear certified?
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General's answer to a question asked in the mitchell inst interview.
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Weatherington's answer was super vague. Oscillating between IOC and FOC dates.
 

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