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Cost per plane comes down when they do a bigger production run, as the initial R&D is amortized over a bigger fleet. B-2 orders were reduced which raised per-p

Cost per plane comes down when they do a bigger production run, as the initial R&D is amortized over a bigger fleet. B-2 orders were reduced which raised per-plane costs

Teever 3y ago
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.
- jandrewrogers 3y ago
  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. [0] https://en.wikipedia.org/wiki/GBU-39_Small_Diameter_Bomb https://en.wikipedia.org/wiki/GBU-39_Small_Diameter_Bomb
  - Teever 3y ago
    Yes really. If the mission calls for x kg of bombs then a plane that carries x/2 kgs is insufficient and you'll need to send two planes.
    - giantrobot 3y ago
      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.
      - Teever 3y ago
        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. I think we're talking past each other.
        cirrus3 3y ago
        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".
        Teever 3y ago
        But you can put those more precise bombs in other aircraft. And if your target calls for twice as many bombs as a B-21 can carry, you're sending multiple B-21s or something else.
        cirrus3 3y ago
        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.
        giantrobot 3y ago
        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."
- JumpCrisscross 3y ago
  > you need twice as many planes to accomplish the same mission Silo-based missiles are for carpeting. Bombers are for stealth, precision, optionality and messaging.
- zardo 3y ago
  And that mission, if understand it,is dropping hydrogen bombs a few hours later than the ICBM and hypersonic bombs hit on doomsday.
- cirrus3 3y ago
  Not really, you are assuming they are using the exact same bombs and just switching out the planes. It is like saying a a iPod Nano will never work because you still need to find a way to fit a spinning HDD in it.
- dragonwriter 3y ago
  > 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.

Cost per plane comes down when they do a bigger production run, as the initial R&D is amortized over a bigger fleet. B-2 orders were reduced which raised per-plane costs

Teever 3y ago

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.

jandrewrogers 3y ago
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. [0] https://en.wikipedia.org/wiki/GBU-39_Small_Diameter_Bomb https://en.wikipedia.org/wiki/GBU-39_Small_Diameter_Bomb
- Teever 3y ago
  Yes really. If the mission calls for x kg of bombs then a plane that carries x/2 kgs is insufficient and you'll need to send two planes.
  - giantrobot 3y ago
    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.
    - Teever 3y ago
      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. I think we're talking past each other.
      - cirrus3 3y ago
        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".
        Teever 3y ago
        But you can put those more precise bombs in other aircraft. And if your target calls for twice as many bombs as a B-21 can carry, you're sending multiple B-21s or something else.
      - cirrus3 3y ago
        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.
      - giantrobot 3y ago
        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."
JumpCrisscross 3y ago
> you need twice as many planes to accomplish the same mission Silo-based missiles are for carpeting. Bombers are for stealth, precision, optionality and messaging.
zardo 3y ago
And that mission, if understand it,is dropping hydrogen bombs a few hours later than the ICBM and hypersonic bombs hit on doomsday.
cirrus3 3y ago
Not really, you are assuming they are using the exact same bombs and just switching out the planes. It is like saying a a iPod Nano will never work because you still need to find a way to fit a spinning HDD in it.
dragonwriter 3y ago
> 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.