Northrop Grumman B-21 Raider (LRS-B)

[paralay]

Sweep angle is 35, not 40. Distortion due to most spotters position play tricks. Hence while wingspan is 48 m, lenght is less, about 20-21 m.

And yes, there are some problems with the long one

 

[Josh_TN]

Then what's up with the Common in the name?

I had assumed it was common across multiple bombers, but I suspect now it means common across strategic weapons for B-52 carriage. IE, bombs or cruise missiles (or SRAM, back in the day).

 

[Josh_TN]

Weird that they seem to have some parts in common, at least, to judge by the contracts I see. But yeah, I think I finally figured out my confusion.

I think the CSRL was common across the B-52 and B-1, back when the B-1 still could carry ALCM.

I would assume that moving the bulkhead forward and having a longer bomb bay for ALCM involved using the CSRL rather than...whatever the B-1 rotary launcher is (forgot the name). MKellyTX could tell us.

ETA: I wonder if B-21 will use CSRL to standardize the fleet or use yet another rotary launcher? Would the length of the bay we are seeing be consistent with CSRL?

 

[NeilChapman]

Sweep angle is 35, not 40. Distortion due to most spotters position play tricks. Hence while wingspan is 48 m, lenght is less, about 20-21 m.

So it looks like my ceiling tiles trumped your taxiway plate...

;-)

 

[bobthemonkey]

As of 2010, there were reports that PW9000 was a gearless derivative of the PW1000G. Two sizes were mooted -- one at 15,000lbf and one at 30,000lbf. That second one was proposed as a fighter replacement engine saving 18% in fuel compared to existing F100 engines. That seems like a reasonably close fit to Sweetman's PW9000 (27k lbf) in the article. Probably not even 4:1 bypass but still way more efficient than the F118.

The smaller of those two options is rather close to the larger PW800 variants in production for Gulfstream. The PW815 is a PW1000G derived core with a gearless fan section, albeit at a ~5:1 rather than 4:1 bypass ratio, producing about 16,000lbf.

If the overall thrust requirement was still around 60,000lbf overall, it’s possible they went with a 4 engine (2x groups of 2) setup lifted from the B2.

You could argue that it gave engine out capability or lower overall fuselage height.

 

[flateric]

And yes, there are some problems with the long one

...and that's why try to redraw with 35 sweep angle...

 

[flateric]

ETA: I wonder if B-21 will use CSRL to standardize the fleet or use yet another rotary launcher? Would the length of the bay we are seeing be consistent with CSRL?

not so obvious pros as it turned out to be back then and killed an idea

 

[flateric]

Weird that they seem to have some parts in common, at least, to judge by the contracts I see. But yeah, I think I finally figured out my confusion.

I think the CSRL was common across the B-52 and B-1, back when the B-1 still could carry ALCM.

Boeing B-52H Stratofortress

Later modifications made it possible for the B-52H to be able to carry eight more AGM-86B missiles internally in a Common Strategic Rotary Launcher (CSRL), which was not fitted to the B-52G. CSRL-equipped B-52Hs can therefore carry up to 20 AGM-86B cruise missiles (8 on the CSRL, plus six each on the underwing pylons. The CSRL program began in 1988 and the first CSRL-equipped B-52Hs appeared later that year. The rotary launcher is fitted inside the bomb bay and is attached to yokes. New electrical and hydraulic lines were fitted inside the bomb bay to operate and control the launcher. The launcher and its associated systems weigh approximately 5000 pounds. Instead of a battery of AGM-86Bs, the CSRL can carry as many as four B28 70-350 kT nuclear bombs or as many as eight B61 (10-500 kiloton yield) or B83 (1-2 megaton yield) nuclear bombs. However, the CSRL cannot carry the AGM-129A ACM, which is too big to fit inside the bomb bay. Some 82 of the B-52Hs were provided with CSRL capability. The CSRL is not compatible with either the B-1 or the B-2 bombers.

 

[flateric]

If I understand its right, what should be CSRL on B-52H is called AGMBRL. Rewired AGMBRL with 1760 data bus is CRL.

 

[flateric]

RLA vs. CSRL/CRL

 

[overscan (PaulMM)]

I tided up the topic, fixing broken links where possible.

 

[overscan (PaulMM)]

I stretched Paralay's top view so the leading edge angle is 35 deg.

 

[paralay]

 

[flateric]

It's clearly seen that there are no F-117A platypus nozzle style expansion on B-21.
(C) David Swanson/Reuters

 

[overscan (PaulMM)]

We seem to have missed Aviation Week's take. They seem to be in the 40m wingspan camp. 35 degree leading edge sweep.

Interactive Graphic: Design Features Likely on The B-21 Raider | Aviation Week Network

A microcutaway of what we think we know about features on the U.S. Air Force’s next stealth bomber.

aviationweek.com

 

[overscan (PaulMM)]

Why the new B-21 Raider stealth bomber looks the way it does

Return of the High-Level Bomber Credit: Northrop Grumman Stephen Liddle looks into the surprisingly long story that led to the first flight of …

hushkit.net

 

[Scott Kenny]

It's clearly seen that there are no F-117A platypus nozzle style expansion on B-21.
(C) David Swanson/Reuters

Of course, with a fairly high bypass ratio (at least compared to the 0.34:1 of an F404), there's less need for the super-expansion nozzle to drop temperature.

 

[paralay]

We seem to have missed Aviation Week's take. They seem to be in the 40m wingspan camp. 35 degree leading edge sweep.

 

[Josh_TN]

We seem to have missed Aviation Week's take. They seem to be in the 40m wingspan camp. 35 degree leading edge sweep.

If the wingspan is 40m, roughly what is the length of the bomb bay doors?

 

[overscan (PaulMM)]

If the wingspan is 40m, roughly what is the length of the bomb bay doors?

I get 240 pixels compared to 1600 pixels on AvWeek drawing. That means 6m at absolute maximum (measured as the length of the door edge).

Assuming the drawing is accurate a 48m wingspan would give 7.2m maximum for the bomb bay.

 

[overscan (PaulMM)]

Doing a similar rough approximation on the B-2 gives me somewhere around 7m for the B-2 bay length.

Assuming the internal bays are identically sized in length (big assumption, I know) that would make the wingspan about 46.66m which is 153ft which just 1ft from my guess for wingspan before actually even seeing it of 154 ft.

 

[paralay]

An option with the placement of air-to-air missiles on a revolver launcher. 8 LRSO + 4 AIM-120

 

[Josh_TN]

I get 240 pixels compared to 1600 pixels on AvWeek drawing. That means 6m at absolute maximum (measured as the length of the door edge).

Assuming the drawing is accurate a 48m wingspan would give 7.2m maximum for the bomb bay.

it seems unlikely the 6m figure could be accurate, unless LRSO is shorter than AGM-86. I’m a little skeptical of the AvWeek dimensions.

 

[Scott Kenny]

If [AvLeak's guess] the wingspan is 40m, roughly what is the length of the bomb bay doors?

First answer:

I get 240 pixels compared to 1600 pixels on AvWeek drawing. That means 6m at absolute maximum (measured as the length of the door edge).

Reply:

it seems unlikely the 6m figure could be accurate, unless LRSO is shorter than AGM-86. I’m a little skeptical of the AvWeek dimensions.

Yeah, I don't believe AvLeak on this one.

I'm expecting LRSO to be AGM-86B length (6.3m), which more or less requires a B-52 sized bomb bay.

Assuming the [AvLeak] drawing is accurate a 48m wingspan would give 7.2m maximum for the bomb bay.

That's a better number, IMO. Rotary launchers need to be significantly longer than the weapons they carry, as the entire spine can come out of the aircraft to be loaded/unloaded.

Doing a similar rough approximation on the B-2 gives me somewhere around 7m for the B-2 bay length.

Assuming the internal bays are identically sized in length (big assumption, I know) that would make the wingspan about 46.66m which is 153ft which just 1ft from my guess for wingspan before actually even seeing it of 154 ft.

I'm not sure that's a big assumption. I'd expect that NG would reuse as much of the existing B-2 weapons racks as possible, which implies bays close to the same size.

 

[Josh_TN]

Perhaps another way of looking at this is to compare bomb bay door width between B-2/B-21. It isn’t clear exactly what rotary would be used or what its length would be, but presumably the Smart Bomb Assembly rack is used and requires a similar width*. Is the length : width ratio the same between B-2 and B-21 bomb bays?

*ETA: and the rotary launchers probably all have more less the same widths as well, at least for our rough measuring purposes.

 

[Scott Kenny]

Perhaps another way of looking at this is to compare bomb bay door width between B-2/B-21. It isn’t clear exactly what rotary would be used or what its length would be, but presumably the Smart Bomb Assembly rack is used and requires a similar width. Is the length : width ratio the same between B-2 and B-21 bomb bays?

That is a very good point.

I feel stupid for not thinking of it...

 

[overscan (PaulMM)]

12 Things We Learned From the New B-21’s Taxi Tests and First Flight

The first flight of the B-21, giving a nearly all-around view, revealed or confirmed many details about how the airplane works.

www.airandspaceforces.com

John Tirpak picks the dimensions as 140ft wingspan, 55ft length.

 

[flateric]

now and then...

 

[RocketJavelin]

Why the new B-21 Raider stealth bomber looks the way it does

Return of the High-Level Bomber Credit: Northrop Grumman Stephen Liddle looks into the surprisingly long story that led to the first flight of …

hushkit.net

Hope you enjoyed it!

 

[overscan (PaulMM)]

Hope you enjoyed it!

It was a good read, Stephen.

 

[aonestudio]

https://twitter.com/x/status/1729682120665141505

View: https://twitter.com/TheDeadDistrict/status/1729682120665141505

 

[Josh_TN]

https://twitter.com/x/status/1729682120665141505

View: https://twitter.com/TheDeadDistrict/status/1729682120665141505

View attachment 712893

I don’t know the context of the presentation or that list, so I am unable to have a truly informed opinion. But if that list is trying to establish where the B-21s technology came from, it seems extremely unlikely most of it is accurate. That list of features covers at least three different aircraft manufacturers (along with weird things like landing gear being mentioned twice). It would be fair to say the B-21 represents a lot of off the shelf technology (tech readiness level 6 or better was required for all systems), and in particular I suspect BAE carried over a lot of its F-35 avionics. And NG makes the radar for the F-35, so I’d be surprised if the B-21 didn’t use the same T/R modules - though the list for some reason mentions the radar as B-2 derived.

All in all it looks like not only a fabrication, but also a fabrication by someone who isn’t familiar with US aircraft production.

 

[NTKV]

That graphic comes from the CSBA (a defense think tank) report were it is labeled as "Illustrative off-the-shelf systems and components for a new bomber" in 2010.

There's two versions: one in the full report and the version that was copied is from a series of slides that can be found here: Sustaining America's Strategic Long Range Strike (slideshare). It's from slide 22.

The graphic predates the B-21 program.

 

[flateric]

...and art by Mike Tsukamoto from A&SFM

The Raider Takes Shape | Air & Space Forces Magazine

Four years into development, the Air Force is starting to reveal more about the B-21 bomber.

www.airandspaceforces.com

 

[quellish]

https://twitter.com/x/status/1729682120665141505

View: https://twitter.com/TheDeadDistrict/status/1729682120665141505

View attachment 712893

This is an LRS-B concept/notional design that was used in, among other places, a CSBA report

https://csbaonline.org/research/publications/americas-strategic-advantage-long-range-strike

 

[Bounce]

Let me guess, they didn't cite their sources?

 

[flateric]

Full Yang's lecture
Post in thread 'Chengdu J-20 news and analysis Part III' https://www.secretprojects.co.uk/threads/chengdu-j-20-news-and-analysis-part-iii.28479/post-637491

 

[Josh_TN]

That graphic comes from the CSBA (a defense think tank) report were it is labeled as "Illustrative off-the-shelf systems and components for a new bomber" in 2010.

There's two versions: one in the full report and the version that was copied is from a series of slides that can be found here: Sustaining America's Strategic Long Range Strike (slideshare). It's from slide 22.

The graphic predates the B-21 program.

Ah, that explains why it doesn’t make much sense in current context and is in English.

 

[bobbymike]

View: https://m.youtube.com/watch?v=Ftba-OC5ojg

 

[MC72]

The Cerberus Flight
In November the long-awaited new Northrop B-21 Raider stealth bomber flies, singularly it is done without the classic veil of secrecy that usually surrounds these important black projects until their total maturation; The reasons for this propaganda display may be due to several reasons, such as a way to give face to the new game changer of the Air Force, which in these complex times are an important asset on the geopolitical level, both for allies and adversaries, It is also important to show the image of a healthy defense industry that is powerful and at the technological forefront, at least one generation ahead in this specialty, when China or Russia are still trying to match the B-2 Spirit of the first generation, which is now 33 years old, The United States launches the second strong generation in addition to all the experience gained from the three-decade operation of the B-2; On the other hand, the maximum secrets that surround the fleeting morphology of the brand new B-21 Raider are not exposed excessively, which in a certain way emphasizes the lines of the old B-2 Spirit, but that surely keeps in its bowels the numerous high-level technologies that are jealously guarded inside.

Even so, the “generous” images of the first flight of the Northrop B-21 Raider allow us to refine a somewhat more precise idea of the general configuration of this new bomber and be able to establish certain concepts:
1- From the new images taken from various angles, it can be established that the B-21 Raider has a single large weapons bay with capacity for a multipurpose rotary launcher (the B-2 has 2)
2- It is also highlighted that the propulsion of this bomber is Bi-engine and not Tetra-engine as in the case of the larger B-2 Spirit; There remains a cloak of secrecy over the selected propellant, which could be a variant of the military PW-9000 derived from the civil PW-1000 family. Another candidate may be a variant based on the PW F-135 used in the F-135 program. 35, and finally there is also the GE XA-100 which is expected to replace some variants of the same PW F-135 (except the STOVL variant).
3- Between the central warehouse and the engine bays appear what appear to be smaller warehouses in the same style as those of the USAF F-22 or the PLAAF J-22, which could be intended for Air-Air weapons and also to additional Air-Ground or Air-Sea attack weaponry. It is not ruled out that in the future they could house energy weapons.
4- The B-21 has its wings angled at 40º degrees and not at 35º as suggested by the previous interpretation of numerous publications to date that replicate the angulation applied to the B-2 Spirit; This greater arrow of the B-21 Raider in its entire configuration suggests higher transonic speed performances than those of the B-2.
This angulation is repeated throughout the perimeter (front and rear, producing a symmetrical central body in the shape of a rhombus with vertices of 100º in the bow and stern and 80º on the sides, which configures a load-bearing body with great volumetric capacity where they are installed. all the specialized elements of this new bomber, the extension of the sides forms the wings with their fuel tanks.
5- The fenestration of the cockpit of the B-21 Raider is particularly small, surely seeking to reduce the surface of these windshields as much as possible with sufficient vision for general flight activities. The cabin internally must have space for the pilot and co-pilot seats. On the other hand, pilots must have electronics that provide them with a very high “Situational Awareness” of high quality provided by both on-board electronics and satellite links or between similar units.
6- Last but not least, it is suggested and not at all unlikely that to increase the deterrent power of this machine that it can fly in “Drone” mode (without a crew), multiplying the capabilities of this bird by not depending on the human resistance, being able to fly long missions solely dependent on in-flight resupply with Tanker Drones, which implies that the 100 planned units can have a 24/7 presence and projection.

Greetings MC72