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tlb wrote:

Loren Pechtel wrote:I'm basically saying to take a recon drone and slap a bubble wall on it and boost it to ultrarelativistic velocity. I do agree it will create a bow wave--but that shockwave is not FTL. Something will have to sense it and get off a warning--but the only ones around who can actually send that warning FTL are the GA. Anyone else it's going to be coming not much faster than the missile.

It's a totally ineffective weapon against ships but it should be very nasty against fortresses.

What is the advantage of a bubble wall (which only allows steering by thrusters) versus an actual impeller wedge driven ship?

I expect (although I am not sure that it is ever stated) that a bubble wall can be seen by the same equipment that can see a low power wedge; since it is the same sort of physics that generates both.

Oops, I meant a buckler. The point is to protect it at velocities beyond which the particle shielding doesn't work.

ThinksMarkedly wrote:And why would anyone develop such a weapon to use against a lesser power than the GA? There are plenty of weapons that work just fine against those lesser powers, notably everything the GA has pioneered. Those new weapons should be developed to work against an enemy that has or will soon have GA-level technology, including FTL comms.

Safer than what they did against the big fortresses.

In any case, the Hastas produced a bowshock at 0.4c. We don't know if that's caused by the wedge or whether anything at that speed through the interplanetary medium will have a bowshock; we also don't know if there's a detection range for those. But the Hastas are exactly what you described: a missile with a recon drone body and its low-power stealthy wedge. So anyone who is a target of those ultra-relativistic kill vehicles would see them coming from very far away, definitely before energy range. Forts can't dodge too much, but they can still dodge a little and they have SD-grade grasers that can reach out to 2.5 light-seconds.

Without FTL comms bow shock detection isn't going to do you any good against an ultrarelativistic kamikaze.

Jonathan_S wrote:1) It does nothing to make the missile more survivable if intercepted by a CM (though, yes, a higher terminal velocity might reduce the odds of that interception a little)

Current recon drones can get very close before they're detected. What I'm proposing is basically a drone, not a missile, it should be equally stealthy. And note what happens if a countermissile does get it--drive blows, the missile is "destroyed"--but the dust cloud has very little time to disperse. The target still takes a beating.

2) It seemingly forces the missile to commit to a ramming attack.

Yes, it's purely a kamikaze. No warhead. Sidewalls reduce lasers, they don't stop them. This would go through them far better than a hot knife through butter. (Which is a bad thing to compare to, anyway--I've actually used a hot knife on various plastic things. It takes time to transfer enough heat.)

The purpose is safely removing things like those giant fortresses.

Daryl wrote:What many avoid thinking about is the second law of thermodynamics along with relativity.
The equation E=MC2 can be rewritten as M=E/C2, so the weight gain that starts to become apparent at 0.9C is made up from enormous quantities of energy. Where does that energy come from? Apparently free from the wedge. My rationalisation is two fold. Firstly it is RFC's universe so he sets the rules, secondly the Honorverse is chronologically as far from us as we are from the ancient Greeks. When you think of all the things we take for granted, that the ancient Greeks would have declared to be magical, it isn't such a great stretch.

Yeah, he handwaved away the energy requirements of relativistic travel. However, that's how the universe works, I'm working within his rules.

cthia wrote:Indeed, but I am considering a missile that has a turbo mode that kicks in right before its final run which quickly accelerates the missile from .8C to damn near light speed. Thousands of missiles accelerating to just under the speed of light at those ranges will be unavoidable once they commit.

An ordinary missile that tries this is destroyed by the failure of it's particle shielding.

cthia wrote:But that dependence might be a result of not being able to reach viable ramming speeds. And those speeds, the god of the HV has decreed, apparently begins at ~ .9C.

You don't need that sort of velocity to ram--you just need a way past the wedge. The logic behind the laserhead made sense in the SDM era, but the MDM changed things--it is almost as survivable ramming as it is at maximum standoff. Sure, it's a sitting duck for the point defenses, but the point defenses will be reloading during that last .2 seconds.

You still need standoff to get around wedges and you might need to use some standoff to avoid fratricide if too many missiles make it through (but I think this unlikely, if they are even tens of microseconds apart there will be no fratricide), but the desired attack should always be ram.

cthia wrote:Actually, that propulsion system makes a lot of sense to me. Theoretically. If a localized black hole can be created and manipulated, it would create an enormous attraction. The logic works for me, if the black hole can be created. In fact, that simply appears to be somewhat of a variation of StarTrek's use of warp nacelles that create a localized phenomena in space time.

Actually, no. Black hole drives look good at a first glance but they have a glaring problem when you look deeper: Tides. Let's say you have a 100m starship, you project a black hole 100m in front of it that gives the ship 100g of acceleration (IIRC the drive in Fury can do a lot better than this.) Is the ship actually in free fall??? Gravity goes at the square of the distance, if it's 100g at the center of the ship it's 100g/.67/.67 at the nose = 225g. The nose of the ship feels 125g, not 0g. The tail has the opposite problem, it's only being pulled at 100g*.75*.75 = 56g and thus experiences -44g. (Yes, this is out of balance, the ship is actually going to be pulled at more than 100g but the exact effect depends on the mass distribution. I could work it out for a uniform cylinder but I'm rusty enough I would have to brute force this and I don't feel like it.)

Ballparking this with a black hole calculator I find an event horizon on the order of a micrometer. It's going to throw off the aim of anything coming from the front but that's all, it's not an impenetrable shield.

tlb wrote:It is ridiculous because the only motion that it imparts to the rest of the ship, is to be drawn into the black hole. So there has to be something that holds the ship out and that has to completely cancel the hole's force on the ship.

Therefore, where does the system get net motion? If an astronaut stands on an asteroid, the two of them do not start moving due to the force the asteroid is imposing on the person; there still has to be an unbalanced force to cause movement. You cannot justify that to me by saying Star Trek does it.

The pseudo black hole is vastly more massive than the ship, it's movement can be ignored.

Jonathan_S wrote:It does nothing to make the missile more survivable if intercepted by a CM (though, yes, a higher terminal velocity might reduce the odds of that interception a little)

Loren Pechtel wrote:Current recon drones can get very close before they're detected. What I'm proposing is basically a drone, not a missile, it should be equally stealthy. And note what happens if a countermissile does get it--drive blows, the missile is "destroyed"--but the dust cloud has very little time to disperse. The target still takes a beating.

A drone will not be as stealthy, if it includes a buckler; which has the same physical characteristics as a sidewall.

I do not think that you have completely thought through what happens with a hit by a counter missile. Yes, the fragments might initially have the momentum of your missile; but the destruction of that missile will also add outward momentum to the elements of that cloud, causing it to spread.

There are also the fragments of the counter missile with its momentum. If those clouds intersect (as is very possible), then much of your impact is gone.

Since we are not completely sure what happens during wedge fratricide, it is further possible that some of the missiles momentum will be canceled by that of the counter missile. If so, you have lost most of your suggested impact.

tlb wrote:I actually mentioned this as the only possible answer the last time I discussed this ridiculous method in this forum. I rejected it then and now, because the energy required to repeatedly create and destroy would be better spent by just moving the ship (and no you cannot regain all the energy needed to create a new one, when you destroy the previous one). This does even begin to discuss the oscillating tidal effects such a process would entail, that are most likely to destroy the ship after killing all life on it.
How do Honorverse ships generate energy?

I don't think those drives are actually creating black holes. Rather, they are gravity projectors, creating a gravitational field of that density but with no mass inside. No energy is involved in the "destruction", you are simply turning off the projector. I actually find the Hammer missiles of the A Learning Experience books more realistic as there's no game of switching them on and off, it's simply a pseudo black hole in front of the missile. It still has the tide and tiny size problem, though.