5 ms·

why did you only quote that part of the paragraph? here's the rest: > Torpedoes are not that much faster than their targets. The Yu-6 is capable of 65 kts in

why did you only quote that part of the paragraph? here's the rest: > Torpedoes are not that much faster than their targets. The Yu-6 is capable of 65 kts in attack mode, but the range figure is for cruise mode, which doesn’t have an associated speed. Even a 65 kt torpedo is only about twice as fast as a carrier, and the sound of the torpedo being fired is enough to alert any ship with a live sonar operator.7 This means that the target ship is likely to be running away, and the submarine has to close to within half of the effective range before launch. Furthermore, the target and its escorts are likely to counterattack, forcing the submarine to evade and cut the torpedo’s wires. A torpedo has limited space for sonar, and without guidance updates from the launching submarine, it can be evaded. All of this is likely to limit submarines to launch ranges of 8 nm or less. he's saying that the effective range for the torpedo is much shorter for a moving target, forcing the sub to get dangerously close. then after being detected, the sub would have to disengage and stop guiding the torpedo, at which point it could possibly be evaded.

CamperBob2 7y ago
Why did you only quote that part of the paragraph? Because that's where it got seriously dumb.
- leetcrew 7y ago
  do you have some relevant expertise to offer? the basic claim that effective range is halved or more against a target moving half as fast as you seems to make sense. I have no idea to what extent torpedoes need guidance from the launcher.
  - CamperBob2 7y ago
    No, I don't, but I'm pretty sure a carrier that's presumably not already "running away" can't hit the gas and accelerate meaningfully when it detects an enemy torpedo launch less than an hour away. Intuitively, evasive maneuvers don't seem to be a useful tool in a carrier's defensive arsenal, but I'd be interested in hearing otherwise.
    - liability 7y ago
      Carriers can move very aggressively for ships of their size: https://www.youtube.com/watch?v=TN7BjeRad2I https://www.youtube.com/watch?v=TN7BjeRad2I At the moment I can't find how long it takes them to step on the gas, maybe that's classified or something, but it's pretty clear they can at least turn around quickly once they're going fast. Of course, deck operations,etc might delay such maneuvers. My guess? If modern warships can't maneuver effectively against traditional torpedoes, Russia would not have spent the money developing supercavitating torpedoes.
      - Retric 7y ago
        That looks impressive, but costs a lot of speed. It’s mostly useful for an aircraft carrier to hide behind another ship rather than directly avoiding torpedoes in open water. As to acceleration they are something like 2.5 HP to the long ton. So picture a 5 HP car on ice.
        liability 7y ago
        There are scenarios where simply being able to stop quickly is evasive. If the torpedo has a 50 km range and the submarine captain assumes it takes you a 1 km to stop, the submarine could attack from 51 km away. When your target is slow to decelerate or change course, you have a greater effective range when attacking from from the front. All forms of acceleration (be it speeding up, slowing down, or turning) will modify the effective range of enemy torpedoes as a function of launch position relative to the ship. Consider even a ship moving at a constant speed and heading. If you draw a line around the ship to represent the maximum range of a constant speed torpedo aimed at the ship, that line won't be circular. If you abstract away water drag and assume submarines can move as fast as carriers, then the line would be circular. But in reality drag on the torpedo means that sub can't simply match speeds with the carrier and expect the speeds of the torpedo and the sub to add up. The torpedoe's top speed is relative to the stationary water, not to its launching submarine.
      - mrep 7y ago
        Step on the gas? They never stop moving! By constantly moving, the airplanes have 30 knots less to accelerate to reach flight speed and 30 knots less to deaccelerate when landing. They're also nuclear powered so it's not like that extra energy actually costs you much.
  - p2detar 7y ago
    The way I read it, that concerns an attack by a single submarine. So what if there are a dozen or more enemy submarine. Is taking out a carrier for 2 or 3 subs a meaningful war exchange?
    - alexhutcheson 7y ago
      A dozen submarines would be an enormous group: China and Russia each only have about a dozen nuclear attack submarines, and non-nuclear submarines don't have the undersea range to get close to a carrier battle group undetected. It would be a huge gamble to throw them all in one attack. The other problem is that the submarines would have no way to communicate without giving away their position. It would be very difficult to execute any sort of coordinated operation.
      - p2detar 7y ago
        Thanks! (Not sure why the downvotes, it was an honest question.)
  - Retric 7y ago
    An obvious counter example is Aircraft carriers need to refuel for their aircraft regularly and can’t travel quickly during this process. Nor can they accelerate quickly if caught in such a situation. Further, to be useful aircraft carriers need to stay near their targets and a few subs acting in concert can lie in it’s probable path. Think one sub every ~30 miles in a line sweeping slowly and they can close the trap. On top of that subs can also launch missiles not just torpedo’s.
    - alexhutcheson 7y ago
      > On top of that subs can also launch missiles not just torpedo’s. From the blog post: "Or can they avoid this by using missiles? Unfortunately, this is not likely to be a healthy choice. At best, an SSN might be able to fire 18 missiles in a single salvo. Even with the benefit of popping up close to the target (which requires going through a lot of those same defenses they’re trying to avoid), this is unlikely to be enough. Launching missiles is extremely noisy, and Aegis is set up to take cues from sonar. The missiles will likely be shot down, and the patch of sea the submarine launched from is not going to be a safe place."
      - Retric 7y ago
        Limits like 18 missiles are very easy to change in a war. Firing 100 vs 18 does not involve some huge leaps in technology, just a different focus. Subs are extremely dangerous places or be in a war and should expect heavy casualties. However, from a military standpoint if the sub is destroyed after taking out an aircraft carrier that’s a major win.
    - wbl 7y ago
      You forgot the sub attached to the carrier is hunting for those subs, and planes can fly quite far. Missiles have to deal with CIWS and RAM.
      - Retric 7y ago
        Several ways around CIWS. Simply having enough missiles in the air works, but you can also do things like add armor or even forgo high explosive payloads relying instead on kinetic energy. Aircraft carriers are huge targets and it's the weapon systems you don't know about that are the largest risks.
trhway 7y ago
>> Torpedoes are not that much faster than their targets. 200knots speed, 6-9 miles range: https://en.wikipedia.org/wiki/VA-111_Shkval https://en.wikipedia.org/wiki/VA-111_Shkval
- alexhutcheson 7y ago
  That gives pretty much the same range as the '8 nm or less' estimate in the blog.
  - trhway 7y ago
    I was addressing just the issue of speed. The torperdoes aren't intended against carriers really. The carrier groups are supposed to be attacked by something like submarine launched self organizing packs of antiship supersonic missiles like https://en.wikipedia.org/wiki/P-800_Oniks https://en.wikipedia.org/wiki/P-800_Oniks. An attack submarine like https://en.wikipedia.org/wiki/Yasen-class_submarine https://en.wikipedia.org/wiki/Yasen-class_submarine carries 32 missiles and can launch 8 per salvo (the VLS launchers are revolver type, so the delay between salvos is very short) from 100km distance in the low-altitude sea-skimming mode. Such an attack would present serious challenge to the carrier group defenses. It is basically machine against machine - automated CIWS vs. the missiles incoming at 2.5Mach (and the new generation of hypersonic missiles is coming https://en.wikipedia.org/wiki/BrahMos https://en.wikipedia.org/wiki/BrahMos), and humans have no role in such engagement.

CamperBob2 7y ago

Why did you only quote that part of the paragraph? Because that's where it got seriously dumb.

leetcrew 7y ago
do you have some relevant expertise to offer? the basic claim that effective range is halved or more against a target moving half as fast as you seems to make sense. I have no idea to what extent torpedoes need guidance from the launcher.
- CamperBob2 7y ago
  No, I don't, but I'm pretty sure a carrier that's presumably not already "running away" can't hit the gas and accelerate meaningfully when it detects an enemy torpedo launch less than an hour away. Intuitively, evasive maneuvers don't seem to be a useful tool in a carrier's defensive arsenal, but I'd be interested in hearing otherwise.
  - liability 7y ago
    Carriers can move very aggressively for ships of their size: https://www.youtube.com/watch?v=TN7BjeRad2I https://www.youtube.com/watch?v=TN7BjeRad2I At the moment I can't find how long it takes them to step on the gas, maybe that's classified or something, but it's pretty clear they can at least turn around quickly once they're going fast. Of course, deck operations,etc might delay such maneuvers. My guess? If modern warships can't maneuver effectively against traditional torpedoes, Russia would not have spent the money developing supercavitating torpedoes.
    - Retric 7y ago
      That looks impressive, but costs a lot of speed. It’s mostly useful for an aircraft carrier to hide behind another ship rather than directly avoiding torpedoes in open water. As to acceleration they are something like 2.5 HP to the long ton. So picture a 5 HP car on ice.
      - liability 7y ago
        There are scenarios where simply being able to stop quickly is evasive. If the torpedo has a 50 km range and the submarine captain assumes it takes you a 1 km to stop, the submarine could attack from 51 km away. When your target is slow to decelerate or change course, you have a greater effective range when attacking from from the front. All forms of acceleration (be it speeding up, slowing down, or turning) will modify the effective range of enemy torpedoes as a function of launch position relative to the ship. Consider even a ship moving at a constant speed and heading. If you draw a line around the ship to represent the maximum range of a constant speed torpedo aimed at the ship, that line won't be circular. If you abstract away water drag and assume submarines can move as fast as carriers, then the line would be circular. But in reality drag on the torpedo means that sub can't simply match speeds with the carrier and expect the speeds of the torpedo and the sub to add up. The torpedoe's top speed is relative to the stationary water, not to its launching submarine.
    - mrep 7y ago
      Step on the gas? They never stop moving! By constantly moving, the airplanes have 30 knots less to accelerate to reach flight speed and 30 knots less to deaccelerate when landing. They're also nuclear powered so it's not like that extra energy actually costs you much.
- p2detar 7y ago
  The way I read it, that concerns an attack by a single submarine. So what if there are a dozen or more enemy submarine. Is taking out a carrier for 2 or 3 subs a meaningful war exchange?
  - alexhutcheson 7y ago
    A dozen submarines would be an enormous group: China and Russia each only have about a dozen nuclear attack submarines, and non-nuclear submarines don't have the undersea range to get close to a carrier battle group undetected. It would be a huge gamble to throw them all in one attack. The other problem is that the submarines would have no way to communicate without giving away their position. It would be very difficult to execute any sort of coordinated operation.
    - p2detar 7y ago
      Thanks! (Not sure why the downvotes, it was an honest question.)
- Retric 7y ago
  An obvious counter example is Aircraft carriers need to refuel for their aircraft regularly and can’t travel quickly during this process. Nor can they accelerate quickly if caught in such a situation. Further, to be useful aircraft carriers need to stay near their targets and a few subs acting in concert can lie in it’s probable path. Think one sub every ~30 miles in a line sweeping slowly and they can close the trap. On top of that subs can also launch missiles not just torpedo’s.
  - alexhutcheson 7y ago
    > On top of that subs can also launch missiles not just torpedo’s. From the blog post: "Or can they avoid this by using missiles? Unfortunately, this is not likely to be a healthy choice. At best, an SSN might be able to fire 18 missiles in a single salvo. Even with the benefit of popping up close to the target (which requires going through a lot of those same defenses they’re trying to avoid), this is unlikely to be enough. Launching missiles is extremely noisy, and Aegis is set up to take cues from sonar. The missiles will likely be shot down, and the patch of sea the submarine launched from is not going to be a safe place."
    - Retric 7y ago
      Limits like 18 missiles are very easy to change in a war. Firing 100 vs 18 does not involve some huge leaps in technology, just a different focus. Subs are extremely dangerous places or be in a war and should expect heavy casualties. However, from a military standpoint if the sub is destroyed after taking out an aircraft carrier that’s a major win.
  - wbl 7y ago
    You forgot the sub attached to the carrier is hunting for those subs, and planes can fly quite far. Missiles have to deal with CIWS and RAM.
    - Retric 7y ago
      Several ways around CIWS. Simply having enough missiles in the air works, but you can also do things like add armor or even forgo high explosive payloads relying instead on kinetic energy. Aircraft carriers are huge targets and it's the weapon systems you don't know about that are the largest risks.

trhway 7y ago

>> Torpedoes are not that much faster than their targets. 200knots speed, 6-9 miles range: https://en.wikipedia.org/wiki/VA-111_Shkval https://en.wikipedia.org/wiki/VA-111_Shkval

alexhutcheson 7y ago
That gives pretty much the same range as the '8 nm or less' estimate in the blog.
- trhway 7y ago
  I was addressing just the issue of speed. The torperdoes aren't intended against carriers really. The carrier groups are supposed to be attacked by something like submarine launched self organizing packs of antiship supersonic missiles like https://en.wikipedia.org/wiki/P-800_Oniks https://en.wikipedia.org/wiki/P-800_Oniks. An attack submarine like https://en.wikipedia.org/wiki/Yasen-class_submarine https://en.wikipedia.org/wiki/Yasen-class_submarine carries 32 missiles and can launch 8 per salvo (the VLS launchers are revolver type, so the delay between salvos is very short) from 100km distance in the low-altitude sea-skimming mode. Such an attack would present serious challenge to the carrier group defenses. It is basically machine against machine - automated CIWS vs. the missiles incoming at 2.5Mach (and the new generation of hypersonic missiles is coming https://en.wikipedia.org/wiki/BrahMos https://en.wikipedia.org/wiki/BrahMos), and humans have no role in such engagement.