Northrop Grumman B-21 Raider (LRS-B)

[rooster]

Some guys over at Dreamland Resort with a reputation of being well informed seem to think that the windows on the B21 are painted on. While I’m not convinced, they do have a few good points, and I’m curious what the experts here think of it.

Sure they are painted on

View attachment 688703

No they are blocked from the inside. Come on its optics. Look at the reflection off the ceiling in the transparencies. Absolutely not paint. It needs windows just so the pilots can take their visors up and rest their eyes and have a portal to look out of.

 

[rooster]

Wingspan 130 ft
Engines F135

Time to scale it up to 140 to fit the second bay, move both bays back and finally give pilots some place for toilet, lawn chair and microwave

I thought it had two bays but only rotary launchers for 6 cruise missiles?

That's just an educated guess to keep weight down. No knows. It makes a lot of sense though. The one thing I wonder about is how big are the aam bays and how many aim260 it will carry in addition to its payload

 

[flateric]

Look at the reflection off the ceiling in the transparencies. Absolutely not paint.

What a sharp eye!

 

[flateric]

...

 

[Moose]

Latest Check 6 podcsast has in-person impressions from seeing more than just the head-on view.

Podcast: Recapping B-21 Rollout, V-280 Contract Win | Aviation Week Network

Aviation Week editors discuss two of the biggest events of the year for military aviation, how they went down and what they mean for the future.

aviationweek.com

 

[VTOLicious]

Source: https://www.airdatanews.com/new-usaf-flying-wing-b-21-has-key-changes-from-b-2-bomber/

Graham Warwick nails it...

"...But really, it's that shift of volume from above the wing to below the wing that I think is the defining ... Other than size, that's really the defining difference, I think, for me on the B-21..."

 

[flateric]

It seems not quite correct to compare these two views taken from very different distances, from very different angles and with very different focal lenghts.

 

[flateric]

I can safely say now that span is more than 42.5 m. Beast is growing up every day)

 

[VTOLicious]

It seems not quite correct to compare these two views taken from very different distances, from very different angles and with very different focal lenghts.

True, but it fits the quote.

 

[overscan (PaulMM)]

I can safely say now that span is more than 42.5 m. Beast is growing up every day)

That's 139 ft+ . You'll get to 150ft eventually

 

[Dagger]

It may have been posted in this topic in the past, I don't know, but I will post it anyway.
Below is a preliminary estimate from december 2019 of how the B-21 would look like and how big/small it would be, based on "public comments and/or public reports" as they call it.

We know now that the inlets and the windows are different, but the reason I post it is merely to illustrate that a flying wing that has only a slightly smaller span and fuselage length can be considerably smaller in total total size.

The B-21 in the image has about 140 ft span, but the total weight is likely to be only about two-thirds of that of the B-2.
Note also that the roll-out showed that the B-21 has only half the number of main undercarriage wheels of the B-2 so there must be a considerable difference in weight.

According to the text: "The B-21 is believed to be somewhat smaller than the B-2, with a payload of around 30,000-pounds, just large enough to carry one GBU-57 Massive Ordnance Penetrator precision-guided conventional bomb, the largest in the Air Force inventory."

It seems only one bomb bay instead of two, and more fuel capacity to achieve longer range than B-2.

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

Yes, I know this is three years old, but be prepared for a disappointment in future when the actual dimensions and payload of the B-21 become public.

 

[Josh_TN]

My money is on single bay of B-2 ish size for the common strategic rotary launcher. USAF wouldn't want to change its loading procedures from the other arm of the bomber force (and the launchers can be loaded sans aircraft with the right equipment which saves a lot of time). Perhaps there will be secondary bays for quick response weapons but I think ~30,000lbs is the warload as previously hinted, just with a larger proportion of fuel to MTOW.

 

[Archibald]

Landing:
The front windows are sufficient for that phase if we do consider that the pilot is seated way in front, close to the openings.
Navigation:
Without doubts, the USAF is planning for a total denial of GPS and wants its bomber to navigate accurately without external help. For a bomber that will fly at very high altitude, the easiest is to have side windows for the navigator that offer panoramic view outside (use terrain reference at great distance and stars). This is probably why the rear windows (the infamous angled ones) are that canted and narrow: when the plane sit noze high at extreme altitude, those are roughly horizontals and allow a rear seated navigator to see plainly outside, beyond the wings.

Obvious to me, this is a tandem seater. Either 1x1, 1x2 or a-la Prowler (2x2).

There is refueling.

But for the life of me they can auto-dock in space at 17,500 mph, and a Tesla can drive me to work. I don't see why automation is not tackled for this procedure. (Just not wBoeing)

A car on earth solid ground is evolving in only two dimensions. No turbulence, at least in the vertical plane. And in space - no turbulence either. It is not a matter of 17500 mph, not between a Soyuz and ISS relative speed at zero or close.
Atmospheric turbulences are a huge PITA.

 

[FighterJock]

My money is on single bay of B-2 ish size for the common strategic rotary launcher. USAF wouldn't want to change its loading procedures from the other arm of the bomber force (and the launchers can be loaded sans aircraft with the right equipment which saves a lot of time). Perhaps there will be secondary bays for quick response weapons but I think ~30,000lbs is the warload as previously hinted, just with a larger proportion of fuel to MTOW.

We won't know how many bay's the B-21 has until the first flight next year so I would not be putting forward a guess right now just in case I get it wrong.

 

[Josh_TN]

My money is on single bay of B-2 ish size for the common strategic rotary launcher. USAF wouldn't want to change its loading procedures from the other arm of the bomber force (and the launchers can be loaded sans aircraft with the right equipment which saves a lot of time). Perhaps there will be secondary bays for quick response weapons but I think ~30,000lbs is the warload as previously hinted, just with a larger proportion of fuel to MTOW.

We won't know how many bay's the B-21 has until the first flight next year so I would not be putting forward a guess right now just in case I get it wrong.

I'm ok with being wrong, so long as my guess is properly marked as such.

I don't know that first flight will necessarily reveal everything; the surface of the aircraft looks incredibly featureless. It might be that whatever coating/structure is used obscures the lines of any openings from a distance.

 

[Hydroman]

My money is on single bay of B-2 ish size for the common strategic rotary launcher. USAF wouldn't want to change its loading procedures from the other arm of the bomber force (and the launchers can be loaded sans aircraft with the right equipment which saves a lot of time). Perhaps there will be secondary bays for quick response weapons but I think ~30,000lbs is the warload as previously hinted, just with a larger proportion of fuel to MTOW.

We won't know how many bay's the B-21 has until the first flight next year so I would not be putting forward a guess right now just in case I get it wrong.

I'm ok with being wrong, so long as my guess is properly marked as such.

I don't know that first flight will necessarily reveal everything; the surface of the aircraft looks incredibly featureless. It might be that whatever coating/structure is used obscures the lines of any openings from a distance.

Featureless is what you want and the surface finish has a lot of evolution in it to be sure. I am curious regarding the air data system. As an example, the YF-23 only used left/right pitot tubes for flight testing, the air data port orifices were part of the skin panels and the main tube was at the tip of the nose (i.e. Metz's book). The production F-23A was an all flush air data system, no tubes like the F-22/F-35, a lot more work but worth it. I'm sure they also limited the amount of access doors/panels as well. The B-2 ports were the tech of the time.

 

[BDF]

My money is on single bay of B-2 ish size for the common strategic rotary launcher. USAF wouldn't want to change its loading procedures from the other arm of the bomber force (and the launchers can be loaded sans aircraft with the right equipment which saves a lot of time). Perhaps there will be secondary bays for quick response weapons but I think ~30,000lbs is the warload as previously hinted, just with a larger proportion of fuel to MTOW.

Man I dunno, I hope not. Limiting yourself to one bay like that reduces your 2,000lb/5,000lb load out compared to two smaller bays, assuming the same maximum payload. It would be an interesting exercise to compare the volumetric differences between one large B-2 style bay vs. two smaller bays.

 

[paralay]

,

 

[Josh_TN]

Whatever the final weapons bay arrangement is, I'm sure it was carefully considered and well thought out. This program seems to have been exceptionally well run by US DoD standards.

 

[sferrin]

Whatever the final weapons bay arrangement is, I'm sure it was carefully considered and well thought out. This program seems to have been exceptionally well run by US DoD standards.

That's a low bar.

 

[sferrin]

It may have been posted in this topic in the past, I don't know, but I will post it anyway.
Below is a preliminary estimate from december 2019 of how the B-21 would look like and how big/small it would be, based on "public comments and/or public reports" as they call it.

We know now that the inlets and the windows are different, but the reason I post it is merely to illustrate that a flying wing that has only a slightly smaller span and fuselage length can be considerably smaller in total total size.

The B-21 in the image has about 140 ft span, but the total weight is likely to be only about two-thirds of that of the B-2.
Note also that the roll-out showed that the B-21 has only half the number of main undercarriage wheels of the B-2 so there must be a considerable difference in weight.

According to the text: "The B-21 is believed to be somewhat smaller than the B-2, with a payload of around 30,000-pounds, just large enough to carry one GBU-57 Massive Ordnance Penetrator precision-guided conventional bomb, the largest in the Air Force inventory."

It seems only one bomb bay instead of two, and more fuel capacity to achieve longer range than B-2.

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

Yes, I know this is three years old, but be prepared for a disappointment in future when the actual dimensions and payload of the B-21 become public.

I could live with ONE MOP, provided they actually purchase these in quantity. Of course now you need two planes to do the job of one but it is what it is I suppose.

 

[flateric]

The volume of the weapon bay is 50 m3, which is 40% of the airframe. B-2 - 38%

no
just try to draw two rotary launchers
let's start with B-2 ARLs weapon clearances - two cylinders with 7 meters lenght and 1 meter diameter
just for info, there are no any fuel on B-2 here in central body excerpt two small areas in front of inlets - not talking of fuel tanks above weapon bay which is literally empty carbon shell with frames support and giant longitudinal beams on top and bottom connected by V-trusses

 

[flateric]

I could live with ONE MOP, provided they actually purchase these in quantity. Of course now you need two planes to do the job of one but it is what it is I suppose.

About dozen posts here about AF wish since early 2010s to have smaller size MOP substitute achieving similar penetration effects with a booster (or flying into the hole of first one may be)....

 

[paralay]

,

 

[sferrin]

I could live with ONE MOP, provided they actually purchase these in quantity. Of course now you need two planes to do the job of one but it is what it is I suppose.

About dozen posts here about AF wish since early 2010s to have smaller size MOP substitute achieving similar penetration effects with a booster (or flying into the hole of first one may be)....

And I've heard lots of talk but haven't seen any evidence.

 

[Josh_TN]

Let's look at a possible range of weapons for the B-21. What are the possible options?

I think the only weapon I've seen explicitly stated as scheduled to be integrated is the LRSO when it becomes available. Presumably B-61 mod 12 while we're talking about special weapons. I've seen it mentioned once that B-21 won't be nuclear certified when it first enters service; not sure what the USAF's schedule is like for that.

Conventionally there should be enough room for most anything. As for what weapons are prioritized for integration - I'd assume SDB-I/II and the heavier penetrating munitions for bunker busting, since a high altitude stealth platform maximizes the effectiveness of those weapons types. I'd think mk84 JDAM would be needed for flexibility, since there are so many different guidance and fusing options that can be added to the basic bomb body (opens up options like Quickstrike and Quicksink on top of ground attack). Probably AGM-158 for good measure (LRASM?). What I'd really like to know is if any A2A weapons would be integrated.

 

[Hydroman]

Single contractor only, clear requirements, contractor working closely with DOD customer, DOD and Congress working together, not lying to one another and trying to place blame. If there are issues during development, make them known to the program/team, fix or compromise and move forward, do not repeat the A-12 fiasco which was like a really bad reality show.

 

[Forest Green]

The volume of the weapon bay is 50 m3, which is 40% of the airframe. B-2 - 38%

Is this fact, or guesswork?

 

[overscan (PaulMM)]

The volume of the weapon bay is 50 m3, which is 40% of the airframe. B-2 - 38%

Is this fact, or guesswork?

How exactly would paralay be in a place to know this information when nobody has even seen the underside of the aircraft?

It is clearly speculation based on his drawings and analysis.

 

[flateric]

(When you say that B-21 transparencies are STRANGE, just remember Boeing/LM NGB cockpit windows...)

 

[mkellytx]

Whatever the final weapons bay arrangement is, I'm sure it was carefully considered and well thought out. This program seems to have been exceptionally well run by US DoD standards.

That's a low bar.

The vast majority of DoD programs finish within the cost, schedule, performance targets. The problem is the vast majority of programs are not ACAT I programs, which unfortunately go forward with technologies that are not yet ready for prime time then end up with problems since the tech is not yet ready. The difference of the Raider versus other ACAT I programs is that they made sure those technologies were ready.

All that said, the perception is valid since only the ACAT I’s show up in the news…

 

[DrRansom]

A note on the external carriage discussion, there's a world of difference between can externally carry stores and can externally carriage a worthwhile amount a worthwhile distance. There are also benefits to designing something for external carriage in future proofing the payload capability, but that can be handled with a balanced bomber force. (Half stealthy penetrator; half non-stealthy cruise-missile carrier)

I am curious about the window placement, the placement may be signature or may be laser protection. I actually was half-surprised they included windows, but eliminating them was clearly a step too far.

 

[NeilChapman]

.

But for the life of me they can auto-dock in space at 17,500 mph, and a Tesla can drive me to work. I don't see why automation is not tackled for this procedure. (Just not wBoeing)

A car on earth solid ground is evolving in only two dimensions. No turbulence, at least in the vertical plane. And in space - no turbulence either. It is not a matter of 17500 mph, not between a Soyuz and ISS relative speed at zero or close.
Atmospheric turbulences are a huge PITA.

That's not a reason, that's an excuse.

;-)

 

[flateric]

Notice the blue lines on the floor are for the B-2's gear.

How do gou know? I.e. if they are for Spirit, then Raider's smaller MLG wheels track kinda proves that her wingspan is less than B-2s

 

[BlackBat242]

The volume of the weapon bay is 50 m3, which is 40% of the airframe. B-2 - 38%

Is this fact, or guesswork?

How exactly would paralay be in a place to know this information when nobody has even seen the underside of the aircraft?

It is clearly speculation based on his drawings and analysis.

Speculation based on his earlier speculations... which are based on his even earlier preconceptions.

All just so much hot air.

 

[paralay]

,

 

[NCQ]

I don't really get the point of this when we still know extremely little about the B-21. We don't even know how many weapons bays it has, let along what its bays can carry (beyond presumably the LRSO in some fashion). Hell, we still haven't even nailed down wingspan with estimates ranging from less than 130ft up to 150ft.

 

[rooster]

I don't really get the point of this when we still know extremely little about the B-21. We don't even know how many weapons bays it has, let along what its bays can carry (beyond presumably the LRSO in some fashion). Hell, we still haven't even nailed down wingspan with estimates ranging from less than 130ft up to 150ft.

I think my kid can even tell its big enough for two weapons bays. Wingspan is totally utterly irrelevant. The volume of the aircraft is what matters. No we don't know that but its not as small an aircraft as was imagined. The gear are a good barometer. They're not going to put 1 bay in the centerline and leave all that real estate alone. The aircraft would be much smaller and not so much girth underneath. Knowledge people there said it was not significantly smaller than a b2. Clearly 2 bays and clearly also room enough for defensive\offensive aams.

Also the windows have nothing to do with laser protection. My office has windows that turn opaque with the push of a button.... That's been around a long time. The windows are the minimum necessary for the human biology dynamic of needing to look outside when flying... From time to time. Flying isn't like being in a submarine.

 

[sferrin]

I don't really get the point of this when we still know extremely little about the B-21. We don't even know how many weapons bays it has, let along what its bays can carry (beyond presumably the LRSO in some fashion). Hell, we still haven't even nailed down wingspan with estimates ranging from less than 130ft up to 150ft.

I think my kid can even tell its big enough for two weapons bays. Wingspan is totally utterly irrelevant. The volume of the aircraft is what matters. No we don't know that but its not as small an aircraft as was imagined. The gear are a good barometer.

Based on that AvWeek says about 220,000lbs.

 

[Josh_TN]

I don't really get the point of this when we still know extremely little about the B-21. We don't even know how many weapons bays it has, let along what its bays can carry (beyond presumably the LRSO in some fashion). Hell, we still haven't even nailed down wingspan with estimates ranging from less than 130ft up to 150ft.

I think my kid can even tell its big enough for two weapons bays. Wingspan is totally utterly irrelevant. The volume of the aircraft is what matters. No we don't know that but its not as small an aircraft as was imagined. The gear are a good barometer.

Based on that AvWeek says about 220,000lbs.

Presumably a gross weight? About 2/3s of B-2. If the engines are around 40% less thirsty than the 119s, which either PW9000 or unaugmented F135 would be in the ballpark of, you could get most of the weight savings just in fuel ( Wiki says max fuel is 167,000 lbs).