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I guess this means their DF21 uses some onboard optical system for terminal guidance, otherwise there would be no need for a physical mockup that visually resem

by jjk166 5y ago

I guess this means their DF21 uses some onboard optical system for terminal guidance, otherwise there would be no need for a physical mockup that visually resembles the intended target (it would otherwise be much easier to just designate a target region and measure afterwards if it landed in the region). Interestingly this might mean the DF21 is vulnerable to countermeasures that would interfere with the optics like a laser dazzler.

woeirua 5y ago
Not sure I would expect an optical guidance system... Would be pretty much useless >50% of the time (during night, or cloudy periods). More likely to be infrared. Carrier's are big and probably have an obvious thermal contrast against the ocean.
- jjk166 5y ago
  IR is still optical
mytailorisrich 5y ago
According to Wikipedia: "The DF-21D has a range estimated between 1,035 to 1,726 mi (899 to 1,500 nmi; 1,666 to 2,778 km)," So, anyway, to me this sounds like Taiwan invasion scenarios where the US might send aircraft carriers off the coast of China. If so, they would be in range for so many attack scenarios so that they'd be toast sooner than later anyway. So far since WWII the US have successfully deployed aircraft carriers because they always have control of both air and sea so their carriers are relatively safe. But that's academic since the overwhelming probability is that the US would not engage China directly and that China would not engage the US directly either because that would be catastrophic for both sides. If anything all those latest developments is China sending that message again, if needed be.
- jjk166 5y ago
  That assumes that China just keeps firing an infinite number of missiles. In reality, there is some ratio where the tradeoff no longer makes sense. If one cheap missile can sink a multibillion dollar aircraft carrier, that's a good deal. If it takes hundreds of these missiles, that's significantly less useful. Further, carriers aren't wimps. These ships were designed to survive nuclear war, with modern damage control actually sinking a ship with a conventional explosive is incredibly difficult. More likely a hit would just result in minor damage that could be repaired at nearby bases. China stands to gain little from invading taiwan - a small province full of disloyal people whose only economic value is in advanced industry which would be destroyed in a war. America, on the other hand, stands to lose everything if it does not defend Taiwan. The moment America can't be trusted to defend its allies, its hegemony is over. No country has the means to touch America in a conventional war, any victory any other power could possibly hope for would be completely pyrrhic. The only unknown is exactly how much of the other nation would be left standing when the Americans decide to go home. There is no logical reason for America to back down first in a game of geopolitical chicken, and everyone knows it. The only winning move for China is not to play.
  - namelessoracle 5y ago
    For China yes. But China doesnt make the moves, its the person leading the country who does. If Xi decides that the calculus benefits him he might make the move. If he succeeds he moves China to the worlds undeniable number 1 super power. He only needs America to blink. And the appearance right now is that American leadership is completely unwilling to challenge China.
    - jjk166 5y ago
      Xi didn't get to the top of his party's leadership by misidentifying peoples incentives nor by betting everything on people going against their own self interest. Xi wants to rouse chinese nationalism as a stabilizing influence as china prepares to face several serious challenges in the near future, and saber rattling with a distant opponent is a good way to achieve that aim. Actually going to war is unnecessary and indeed runs directly counter to his goals. Further, Xi is not an autocrat; he certainly holds immense influence over the workings of government, but if he loses the faith of the party by a series of irrational decisions, he will be replaced. America, for its part, has essentially named China its primary adversary and focused all efforts on opposing it economically, diplomatically, and militarily, with wide bipartisan support. Maybe America's current leadership would blink, but its a gamble; a gamble in which if Xi wins he gets basically nothing while if he loses his country burns.
      - namelessoracle 5y ago
        I agree with all of this. But if Xi's internal situation with his party denigrates to the point where he needs to take some kind of major action that boosts his stature, that is when trying to invade Taiwan becomes a possibility. China basically gains nothing from invading Taiwan, but Xi might have some things to gain politically to solidify his position in other words.
  - matheweis 5y ago
    > a hit would just result in minor damage that could be repaired at nearby bases. They don’t have a good track record of late: USS Cole - c4 bomb - 2 years USS Fitzgerald - collision - 3 years USS Bonhomme Richard - fire - scrapped

by jjk166 5y ago

woeirua 5y ago

Not sure I would expect an optical guidance system... Would be pretty much useless >50% of the time (during night, or cloudy periods). More likely to be infrared. Carrier's are big and probably have an obvious thermal contrast against the ocean.

jjk166 5y ago
IR is still optical

mytailorisrich 5y ago

According to Wikipedia: "The DF-21D has a range estimated between 1,035 to 1,726 mi (899 to 1,500 nmi; 1,666 to 2,778 km)," So, anyway, to me this sounds like Taiwan invasion scenarios where the US might send aircraft carriers off the coast of China. If so, they would be in range for so many attack scenarios so that they'd be toast sooner than later anyway. So far since WWII the US have successfully deployed aircraft carriers because they always have control of both air and sea so their carriers are relatively safe. But that's academic since the overwhelming probability is that the US would not engage China directly and that China would not engage the US directly either because that would be catastrophic for both sides. If anything all those latest developments is China sending that message again, if needed be.

jjk166 5y ago
That assumes that China just keeps firing an infinite number of missiles. In reality, there is some ratio where the tradeoff no longer makes sense. If one cheap missile can sink a multibillion dollar aircraft carrier, that's a good deal. If it takes hundreds of these missiles, that's significantly less useful. Further, carriers aren't wimps. These ships were designed to survive nuclear war, with modern damage control actually sinking a ship with a conventional explosive is incredibly difficult. More likely a hit would just result in minor damage that could be repaired at nearby bases. China stands to gain little from invading taiwan - a small province full of disloyal people whose only economic value is in advanced industry which would be destroyed in a war. America, on the other hand, stands to lose everything if it does not defend Taiwan. The moment America can't be trusted to defend its allies, its hegemony is over. No country has the means to touch America in a conventional war, any victory any other power could possibly hope for would be completely pyrrhic. The only unknown is exactly how much of the other nation would be left standing when the Americans decide to go home. There is no logical reason for America to back down first in a game of geopolitical chicken, and everyone knows it. The only winning move for China is not to play.
- namelessoracle 5y ago
  For China yes. But China doesnt make the moves, its the person leading the country who does. If Xi decides that the calculus benefits him he might make the move. If he succeeds he moves China to the worlds undeniable number 1 super power. He only needs America to blink. And the appearance right now is that American leadership is completely unwilling to challenge China.
  - jjk166 5y ago
    Xi didn't get to the top of his party's leadership by misidentifying peoples incentives nor by betting everything on people going against their own self interest. Xi wants to rouse chinese nationalism as a stabilizing influence as china prepares to face several serious challenges in the near future, and saber rattling with a distant opponent is a good way to achieve that aim. Actually going to war is unnecessary and indeed runs directly counter to his goals. Further, Xi is not an autocrat; he certainly holds immense influence over the workings of government, but if he loses the faith of the party by a series of irrational decisions, he will be replaced. America, for its part, has essentially named China its primary adversary and focused all efforts on opposing it economically, diplomatically, and militarily, with wide bipartisan support. Maybe America's current leadership would blink, but its a gamble; a gamble in which if Xi wins he gets basically nothing while if he loses his country burns.
    - namelessoracle 5y ago
      I agree with all of this. But if Xi's internal situation with his party denigrates to the point where he needs to take some kind of major action that boosts his stature, that is when trying to invade Taiwan becomes a possibility. China basically gains nothing from invading Taiwan, but Xi might have some things to gain politically to solidify his position in other words.
- matheweis 5y ago
  > a hit would just result in minor damage that could be repaired at nearby bases. They don’t have a good track record of late: USS Cole - c4 bomb - 2 years USS Fitzgerald - collision - 3 years USS Bonhomme Richard - fire - scrapped