> It's almost important to note that this new B-21 has half the bomb capacity of the B-2.
> So that means that you need twice as many planes to accomplish the same mission.
Yes, in the limit case where you need the full bomb capacity of the B-2 for a mission, that is correct.
OTOH, the B-2 itself has a little over half the payload capacity of the B-52, which unlike the B-1 and B-2, is not planned to be replaced by the B-21. The point of the B-21 is not to get the maximum load per plane, its to maximize the certainty of delivering the load in a contested environment, in large part to create the kind of uncontested environment in which you can just freely drive in B-52s if you need quantity per plane.
Not really, it will be used almost exclusively to deliver very smart, very precise weapons that are smaller and lighter than what they replace. See, for example, the Small Diameter Bomb[0] program. In this capacity raw tonnage matters less. When the B-2 was designed, the ordnance options were a lot more limited, bulkier, and heavier.
Bombing missions are about destroying targets, not meeting some quota of explosives dropped. Precision bombs require far fewer units and a lower mass of explosives to destroy a target than dumb bombs.
This is all true, but if your target still requires twice as many bombs of whatever technology than your aircraft can hold you will need to send two planes.
We're not really. With modern targeting systems an unguided bomb like a Mk.82 has a precision (circular area probable, CEP) 30-50m in perfect conditions. The same Mk.82 with a JDAM kit attached has a CEP of around 4-5m.
Just to be sure you hit a target with unguided bombs you need to drop several at once. Missing a building by 50m is the difference between hitting it or its parking lot. That same mission could be done with a single guided bomb because it's more likely than not going to hit exactly where it's aimed. In Iraq JDAMs were sometimes targeted at individual vehicles.
A B-21 with fewer smart bombs has a higher likelihood of destroying all of its targets than a B-2 loaded with a larger number of dumb bombs.
In terms of Nuclear Triad, having more airframes is more important than carrying more weapons. With a larger number of B-21s able to operate at more airfields they're a more credible threat than a small number of B-2s. In nuclear deterrence you want the other side to think "Damn, there could be bombers overhead right now waiting to nuke me if I push the button. Maybe I'll talk this out instead."
Per this example, the B2 isn’t being used in any real capacity, so it’s not really relevant to compare it, especially for conventional weapons. As of late 2010s, the B1 and drones did the preponderance of munitions drops in the Middle East, and just about all of those drops were using some form of guided munitions. I’m not even sure we use unguided in any real capacity.
Source: was there, saw it. The exclusive purpose of the B2 is nuclear strike.
I think you're talking past each other because you're assuming 100% of bombs are hitting their target and the other person is not.
If you need 100kg of bombs for a mission but only 50% of them hit targets, then 50kg will work if you can assume 100% will hit target. That is why precision matters and coul reduce number of planes needed even if the same amount of kg is required.
None of us are probably qualified to make assumptions here, but the basic idea is simple - higher precision Might offset the need for as many planes.
You are also discarding the point about weight. The weight of the bomb is what matters to the plane, destructive power is what matters on the ground... something that took X kg of destructive power to destroy 20 years about may only take X/2 kg if it were more precise or effective in how it used that explosive "weight".
the "cost per plane" is usually the input (total money dedicated by congress including 50 year maintainence window) divided by the output (number of planes). so it looks unusally expensive (f35 prOGrAm coSTs 1.5 TRilLiON DollARS) but the actual materials of the plane is a minute fraction of that nummber which is what people think of when they hear cost.
Wiki also says that B-21 is projected to cost 213B$ for 100 planes over 30 years. So you get 2.13B$ again. Projected costs are also likely to increase (of course! I can't estimate how much time one screen is gonna take me, can't imagine estimating 30 years worth of stuff)
The $203B is the total program cost. It includes the 30 years of operating costs which are more than development and acquisition. The unit cost is currently estimated to be $700 million.
The B-2 $2B is 1992 unit cost. Inflation means more like $4B. Plus, the B-2 are pretty expensive to operate which is why the B-21 will replace the B-2 first.
The Air Force planned to order more than 100 B-2s when the program was started but Congress cut the order down to fewer than two dozen. So the cost per plane ballooned because the development costs had to be amortized of a smaller number of airframes.
basically military budget will always eat 1/4 to 1/3 of the US budget no matter the output, so if it produces few dozen F35 then yes - it will look like costs per unit are outrageous.
a lot of military spending is fixed costs that pentagon is unable to dial down, has to spend due to contracts and maintenance, and basically jobs + pork barrel program.
so they just play "hollywood accounting" tricks by allocating their spend from line item A to line item B, depending on what voters will bear.
one decade it will be Afghanistan war, another decade it will be airforce development, this upcoming decade it will be Navy spending on new boats etc.
Much of the cost in per unit is due to initial capex (e.g. R&D and tooling). I would hope they're reusing many of the things from the first version. This would make the new version much cheaper per unit.
But agreed that cost is likely to balloon, both government and defense contractors are incentivized for it to balloon (it's a lucrative jobs program for many across many states).
The rule of thumb from my senior aircraft design course was that 90% of the cost is designed in before you bend the first piece of sheet metal. Commercial programs have their own guidelines about how many planes you have to make to break even, and even there where they aren’t radically pushing the envelope it’s on the order of hundreds.
Cool graphic! Watched a video about F-35 [1] yesterday, it goes over many of the considerations in building for stealth (e.g. avoid 90° angles). It's also why they put engine intakes on the top for the B-2, as radar stations are on the ground.
I wonder if defense departments are starting to put receivers (or transmitters or both) in space to work together with ground stations.
Just to elaborate, the B-2 has the shape it does because it was designed for two missions, one flying at high altitude, the other at low. This requirement significantly complicated the aerodynamics, however the low level penetration mission is now regarded as suicidal, hence, the B-21 is designed for high altitude alone.
What's the benefit of low-altitude capabilities for these bombers? Increased accuracy/precision? I would think that modern bombers would be incredibly accurate in any situation.
At one time low altitude was the best way to evade air defense as fighters didn't have look down/shoot down radar capability. They do now, so the low altitude mission might help with ground based radar (by using the earth and geographic features to hide), but an enemy with modern fighters and AWACS capability makes this profile difficult.
When computers sucked and there were a lot fewer smart bombs/missles, flying low gave you extra accuracy, but now that modern bombs include gps, IR, and probably 6 other tracking technologies it's a lot less useful.
Russian and Chinese Surface to Air Missile (SAM) systems are really good. Modern versions can detect and target most stealth aircraft at a range of 15-35 miles, depending on radar cross section and electronic countermeasures in use.
Not correct because of physics. Ground based radar is still blocked by terrain and the horizon, meaning that low altitude attacks are still quite effective against only ground defense. That is why Ukraine's air force still exists and is still causing issues for Russia. It is also why shaheed drones are causing problems for Ukraine.
The bigger problem for low altitude attack is AWACS + fighters and interceptors with look down/shoot down capability. The MIG-31 has been a major problem for Ukraine because it has long range radar + long range missiles that can hit low targets. NATO and other US allies have integrated air defense where data from AWACS and other aircraft can be used to target low altitude targets.
As far as stealth goes, the notion that stealth aircraft can be targeted at medium ranges has not been tested on the battlefield.
> Russian and Chinese Surface to Air Missile (SAM) systems are really good
Their radars seem good. Russian “hypersonic” missiles [1] and S-400 batteries [2] are being taken out by decades-old Patriots and ATACMS. They’re demonstrably garbage.
The Russian and Chinese air defense systems might detect but not target at a long enough range to matter. Those are two different tasks and fundamentally how stealth works in practice. Knowing an aircraft is out there does no good if you can't resolve a firing solution. Detecting at a range of 15-30 miles is a small comfort when an F-35 can carry anti-SAM missiles with a range of 100 miles.
There is also quite a bit of empirical evidence in recent months that the Russian systems do not work that well generally, since they seem to be incapable of defending themselves against non-stealth Cold War era US tech.
When you're flying low, stealth doesn't work because people can look up and see you (and then your 2 billion dollar bomber gets brought down by a 20k dollar shoulder mounted weapon).
Stealth reduces detection range, it does not eliminate it. If an adversary has information on the path the target is likely to take it makes things much easier. This is how a F-117 got shot down over the Balkans. They kept using the same route and someone figured it out. At the ranges MANPADs operate, a couple km at most, thermal stealth is effectively impossible.
MANPADS do not use radar, they are all infrared or beam riders. You would not expect a B-21 to ever be within range of those weapons, which are really only designed to be used against helicopters and close air support aircraft.
No, those programs are unrelated to the B-21, and the B-21's design phase precedes the existence of the loyal wingman concept. It also doesn't fit the mission profile of the B-21, as it's job is strategic bombing using stealth, which is done solo not in formations. It'll no doubt have networking capabilities with ISR drones to set up kill chains but on mission it will be completely silent in terms of EM emissions.
> The loyal wingman concept will also be extended to the top-secret Northrop Grumman B-21 Raider stealth bomber.
> “The B-21 is a very expensive aircraft. It has a certain payload and range. We would like to amplify that capability. It has the ability to penetrate, which is valuable,” says Kendall. “What we want is something that can go operate with it. I wouldn’t say ‘accompany it’ necessarily. The tactics are very much to be determined.”
Yeah, that's just the usual posturing after programs are already started and everyone tries to hitch to everyone's wagon. The reason why that last sentence is there is even this person knows what they're saying isn't credible vs the actual mission profile of the B-21 and they're doing a PR move to get ahead of that.
At this point in history, what's the point of having a super expensive bomber plane with an actual human pilot vs. having a much cheaper, autonomous, hyper-sonic, and disposable delivery vehicle in the form of a rocket? Flying from A to B with cm. precision is pretty much a solved problem. Doesn't require a human flying a thing.
Why would you fly such a thing in any situation where you might have to risk losing the plane + pilot?
Hypersonic missiles are not cheap. The LRHW that US is putting on land and ships costs $50 million per unit. Its payload is probably a single bomb worth. Its range is 1700 mi. The B-21 costs $500 million. It can carry the same amount of ordinance in one mission as the same cost in hypersonics.
The B-21 can carry multiple, cheaper cruise missiles. It can drop the air-breathing hypersonic cruise missiles whenever those are developed. It can loiter over the battlefield dropping bombs as needed. It can come back and do it the next day. It can fly halfway around the world.
> what's the point of having a super expensive bomber plane with an actual human pilot vs. having a much cheaper, autonomous, hyper-sonic, and disposable delivery vehicle
Russian hypersonic missiles are being shot down by old Patriots [1]. Meanwhile, our commercial autonomous systems—arguably ahead of our military’s—still lag humans.
If we want to bomb someone, land-based missiles are the way to go. They overwhelm defences. And they’ll be just as loud as a hypersonic missile.
Bombers, on the other hand, can fly stealthily. They can also loiter, similar to a carrier strike group, sending a message without provoking MAD.
> Russian hypersonic missiles are being shot down by old Patriots [1].
The "hypersonic missiles" being shot down by Patriots are the kind of ballistic missiles the Patriot was designed to shoot down, they've gotten lumped in as new "hypersonic missiles" (which is technically true of many ballistic missiles) alongside Russia's new hypersonic cruise missile (Zircon) that they were announced alongside as a propaganda technique to magnify the perceived degree of threat, but they aren't the same thing at all.
Kalibr and Kinzhal. Designed and manufactured after the Patriots that shot them down were put into long-term storage. (I don’t think S-400s, either which Moscow sells for half a billion dollars to apparently chumps, were meant to be taken out by decades-old Patriots. )
For reasons ranging from corruption to skills degradation, Russia simply isn’t technologically capable of producing advanced weapons anymore. (They are capable of making the marketing.)
Those were Kalibrs that were supposedly shot down. Only certain variants are hypersonic in the final approach, and that doesn’t mention the variant at all.
Look at how Russia uses their old heavy bombers for an idea: they use them to carry missiles that can be released outside of air defense range. The larger plane reduces the fuel required by the missile (meaning more explosives) and allows the missiles to be positioned and fired faster than a truck or ship can get into position. The idea of flying over the target is kind of old - modern glide bombs (again, use the aircraft's energy instead of reducing payload) have a 20-50km range and are more accurate.
The super expensive stealth bomber lets you move into a very unexpected position and release missiles/glide bombs in a way that may not allow for any air defense work at all.
There's operational/capability benefits that can be rationalized, but in terms of aquisitions it's probably cheaper and politically easier for USAF MIC to build billion dollar bombers, sustained by billion dollar basing and aerial tanking to drop million dollar smart bombs. There's inertia in terms of integration into existing systems and interservice history (drama) with each branch fighting for dollars and relevance over their piece of future long range strike mission. Don't discount the politics - the airforce is not going to NOT have expensive planes supported by expensive tanking fleet. The navy is not going to NOT have expensive carrier groups supported by expensive replenishment. The marines fine with pivotting to maritime strike missions, but they're a small. Army is bigger, have little role in IndoPac (really what B21's about - China), Airforce and Navy going to lobby against Army stepping on their turf.
PRC side stepped that by elevating rocket force (previously artillery corp) as it's own branch, PLA writing on long range strikes is more or less prompt global strike with ICBMs. They also don't really have a another choice since it would take decades to build up alternate power projection methods (carriers, bombers). They're still developing those options but in theory their near term equalizer is to spam 10,000 or even 100,000s of icbms to take out expensive reusable US platforms and other critical targets. And with PRC value engineering, at significantly less cost.
> but in theory their near term equalizer is to spam 10,000 or even 100,000s of icbms
Counting ones under construction (which are the vast majority), China is estimated to have a little under 500 ICBM launchers and probably not significantly more ICBMs than operational launchers. There's zero chance for them to "spam 10,000 or even 100,000s of ICBMs".
ICBM silo force (as in triad) is under Air Force. Army and airforce competed for control over ICBM in the 60s, and airforce ended up getting ICBMs, army engineers built the silos. As far as I know, army doesn't have long range strike options. Army was hampered until recently from even expanding to medium range theater options due to INF. Army's Space Missile Defense Command did test advanced hypersonic weapon AHW a decade ago. Airforce response was, too expensive per unit, too destablizing, basically piss off army, long range strike is our turf.
I read discussion recently that Air Force ICBMs should be transferred to Space Force. Which makes a lot of sense and would spread out the nuclear triad.
The Army is getting medium-range strike. They now have land-based Tomahawk missiles. They are also getting the LRHW hypersonic missiles with 1700 mi range.
The economics, range, and flexibility of a nominal bomb carrier are vastly better than disposable and especially hypersonic delivery platforms. You also have to understand US military doctrine. Platforms like the B-21 are designed to deliver autonomous swarms of stealthy, networked, long-range weapons that can cooperate with each other and adapt to their environment. In this sense, the B-21 is as much a control plane and orchestrator as it is a delivery system.
For offensive systems, the US prefers slower, stealthier missiles rather than hypersonic missiles. While hypersonic missiles arrive on target faster, they have serious deficiencies in terms of precision, terminal guidance, range, and payload size. Consequently, the US has had hypersonic missiles for several decades but relegated them almost exclusively to defensive systems where those limitations matter much less because the target is coming to you. This is an option somewhat unique to the US due to their qualitative advantages in stealth and electronic systems, which they lean into heavily.
The US 6th generation platforms, like the B-21, are all designed to support unmanned operation, the pilot is optional. In a near peer conflict, communication channels may be severely degraded such that having a person in the seat will have value.
Precision is solved, but many of the solutions can be jammed.
What can't be jammed (easily) is laser guidance. The B-21 can fly over a target and a crewmember can point a laser at a target and the bomb will ride the beam down.
Remote laser guidance is difficult due to latency.
The B-21 was designed to operate both manned and unmanned.
It may be possible from low earth orbit but time overhead is, at maximum, 20 minutes. Add in obstructions like terrain and non-ideal look angles and you may be only able to paint a target for several minutes if at all. This would require extraordinary precision and coordination to achieve.
I am comfortable saying that it is realistically impossible from higher orbits.
> At this point in history, what's the point of having a super expensive bomber plane with an actual human pilot vs. having a much cheaper, autonomous, hyper-sonic, and disposable delivery vehicle in the form of a rocket?
Putting munitions on single use hypersonic rockets is a lot more expensive than loading a bunch of them up on a reusable bomber.
Which is one point of bombers: they are logistically superior in an environment in which they are survivable to missiles for the quantity of munitions delivered. That's also why you have both stealth bombers like the B-21/B-2 and then less stealthy, heavier bombers like the B-52 for different environments.
Pilots are, like other parts of the bomber, reusable in the conditions in which the plane is survivable, and the operational cost of pilots is fairly low.
A 2019 RAND study put the cost of bomber pilots on the order of $10 million, which isn't cheap, but when the bomber itself is $2+ billion, doesn't really move the needle on the whole system.
A bomb truck is a cost-effective way to get cruise missiles and such in range from safer out-of-theater air bases. Making it survivable in a contested environment (stealth) opens up lots more mission profiles and lets you use even cheaper munitions like glide bombs and guided bombs, which is especially helpful in a protracted conflict. Plus it requires less escort.
A bomber isn't cheap, but it is cheaper than lots of ICBMs. And, in many cases, than multi-role fighters and/or cruise missiles.
A rocket can't stay on-station for hours at a time waiting for the right moment to deliver the payload. With mid-air refueling, this beast can hover near but out of reach, to produce a threat that may never strike. A nice piece to have when 'negotiating' with a near-peer antagonist.
These B2 Bombers are impressive when they fly over. When we were kids, my brothers and me would always excitedly shout and point at them when we saw them passing by in rural northern Germany. I saw a lot of them back then, probably on mission. I didn't really grasp at that time what seeing them meant.
That's the thing, I am pretty sure sure it's entirely evolutionary, without knowing anything about the project. B-2 with better stealth, engines, software, and hopefully lower maintenance costs.
Still more than any other country accomplished, but this is built on a solid foundation, without much departure. If anything, it's a mature, modernized B-2.
It's completely evolutionary! To add context here. The B-21 is an manned version of a drone called a RQ-180, which is an extremely stealthy flying wing. Coupled to existing engines (widely believed to be F-35 engines possibly with an increased bypass ratio).
The B-2 had this huge problem where the original design (called "Senior Ice") was a stealthy high altitude bomber - like the B-21. But, at the last moment, the B-2 was completely redesigned to have low altitude flying capabilities - greatly increasing the cost of development and timeline.
With the B-21, Northrop reverted to the original (Senior Ice) design. Building on top of all the technologies proved out by the RQ-180. And with a development team at the Strategic Capabilities Office organized to prevent anyone from adding or changing requirements.
Evolutionary design + proven subsystems + focused and stable requirements.
Likely the best managed DoD acquisition program in the last one to two decades.
>the B-21 is an manned version of a drone called a RQ-180
No it's not. The RQ-180 as a HALE drone with no weapons. The B-21 is a dedicated bomber. Despite both being flying wings with roughly the same basic shape the airframe requirements are completely different.
> the B-21 is an manned version of a drone called a RQ-180,
that's interesting, i wonder if that's where the unmanned mode of the B-21 comes from. Being able to fly unmanned would be useful in very high risk scenarios.
That would be too good to be true. It's in fact a smaller airframe with less range. Medium strategic bomber, not a proper one. Will still be good to go because new tankers will provide it with enough range and are available in large numbers.
Nope. Smaller airframe yes, but a design that benefited from decades of advances in both algorithms and computing power. It most likely has a much better lift-to-drag ratio than B2, and more efficient engines too. It will at least match B2's range.
Though the Raider’s true range remains classified, estimates place it at approximately 6,000 miles of range without refuelling, highlighting the platform’s extraordinary global potential.
That is exactly what is needed. The B-2 is too big, too expensive, and too few. The B-21, two thirds the size, is much more useful for modern warfare. The US is planning on buying 100 of them instead of the 21 B-2, and replace the B-2s, B-1s, and maybe the B-52s.
The B-21 has the same range as B-2, it is the B-2 that is shorter range than B-52. Smaller bomber is much more flexible. Most missions don't require B-2 or B-52 size when carrying a few cruise missiles or guided bombs. If do need more, than can send two of them and those are available.
I think that was a calculated move based on what you described and the fact that the US has based these in allied countries during operations, so the full "strategic" range isn't really needed.
B-2 has a unit cost of 2.13B$ (1997 $) = 4.08B$
B-21 has a unit cost of 0.55B$ (2010 $) = 0.78B$
Looks nice right? But projected unit costs for B-2 in 1997 were also 0.74B$ (1997 $) so who knows how it ends up