LAC not so useful after all?

kzt wrote:One (ok, two) quick question on the triple ripple: Wouldn't the missiles be primarily using grav sensors anyhow, which should be totally unaffected by a series of really bright flashes? So I could see some loss of accuracy, but with their primary targeting sensor still up they should still be reasonably effective.

If setting off a really bright flash messes up sensors this much, how come ships don't just fire out a set of huge fusion bombs from their missile tubes to go off just as the missile salvo arrives and the laserheads need to lock up their target? They can't look away at that point.

My understanding is that ships can displace themselves quite a way from the geometric center of their own wedge. So grav sensors aren't good enough because they can only see the wedge, not the actual ship. (Plus I wonder how capable a grav sensor you could cram onto the fairly tiny nose of a missile)

If you blind the terminal targeting sensors it doesn't matter much if the missile still had some grav sensors.

Jonathan_S wrote:My understanding is that ships can displace themselves quite a way from the geometric center of their own wedge. So grav sensors aren't good enough because they can only see the wedge, not the actual ship. (Plus I wonder how capable a grav sensor you could cram onto the fairly tiny nose of a missile)

If you blind the terminal targeting sensors it doesn't matter much if the missile still had some grav sensors.

Sure, ships can displace themselves inside the wedge. But the job of the missile is to deliver the laser heads and warhead to the the general vicinity of the ship, not to find the ship inside the wedge.

The missile deploys the laser heads and focusing elements multiple seconds out, so at say 500,000 km from the target ship the missile drive shuts down, blows the fairings off the laser heads, warhead and focusing elements and they deploy to attack as they scream by the target at 0.8C.

Since missile grav sensors plus the guidance from the launching ship seem perfectly capable of getting the missile to a trajectory where the payload will pass within 50,000 km of the target, I still don't see how the triple ripple works.

Grav sensors are shown in the laser head drawings, so yes, they have them. The laser heads are what need to find and target the ship inside the sidewalls. Comments by Bu9 suggest that the sidewall is effectively opaque to visible light from the outside and you don't usually have enough time to depend on an active sensor even if radar can penetrate the sidewall (you have something like 30 to 250 milliseconds to against a rolled ship to engage from the point where you can see it past the wedge), so you are pretty much going to have to depend on the grav sensors alone.

[I can certainly see times you would use other sensors, but not so much against active warships.]

Anyhow, given that, what you need to blind are the sensors in the laser heads. However these are inside the missile fairing and hence are not going to be affected by the triple ripple. So their optical, radar, lidar and thermal imaging will also be still working, along with the grav sensor.

Now if you do need some other sensor, then having the missile tubes firing out a set of gigaton yield bombs to go off outside the sidewalls at rapid intervals during the ~500 milliseconds when the laser heads should be in firing range (and looking right at the detonations) would seem likely to rather significantly reduce laser head accuracy.

kzt wrote:Sure, ships can displace themselves inside the wedge. But the job of the missile is to deliver the laser heads and warhead to the the general vicinity of the ship, not to find the ship inside the wedge.

The missile deploys the laser heads and focusing elements multiple seconds out, so at say 500,000 km from the target ship the missile drive shuts down, blows the fairings off the laser heads, warhead and focusing elements and they deploy to attack as they scream by the target at 0.8C.

Since missile grav sensors plus the guidance from the launching ship seem perfectly capable of getting the missile to a trajectory where the payload will pass within 50,000 km of the target, I still don't see how the triple ripple works.

Grav sensors are shown in the laser head drawings, so yes, they have them. The laser heads are what need to find and target the ship inside the sidewalls. Comments by Bu9 suggest that the sidewall is effectively opaque to visible light from the outside and you don't usually have enough time to depend on an active sensor even if radar can penetrate the sidewall (you have something like 30 to 250 milliseconds to against a rolled ship to engage from the point where you can see it past the wedge), so you are pretty much going to have to depend on the grav sensors alone.

[I can certainly see times you would use other sensors, but not so much against active warships.]

Anyhow, given that, what you need to blind are the sensors in the laser heads. However these are inside the missile fairing and hence are not going to be affected by the triple ripple. So their optical, radar, lidar and thermal imaging will also be still working, along with the grav sensor.

Now if you do need some other sensor, then having the missile tubes firing out a set of gigaton yield bombs to go off outside the sidewalls at rapid intervals during the ~500 milliseconds when the laser heads should be in firing range (and looking right at the detonations) would seem likely to rather significantly reduce laser head accuracy.

The laser rods themselves definitely need more accuracy that just knowing where the geometric center of the wedge is; but I can see where the missile itself (before it deploys them) doesn't.

I thought I remembered the sidewall's effect as more like "blurring" the ship's location; not being completely opaque. But I can't find that reference quickly...

I played with some numbers, and even if the ship can only move around within 1% of the 2D area between the wedge planes it's a 0.262 square kilometer needle hiding in an over 450 square kilometer haystack. Random distribution give a single laser rod about a 0.0582% chance of a hit. You'd need hundreds of missiles to statistically expect a hit. So clearly the laser rods manage to aim themselves at the ship (somehow) far more accurately than that.


Maybe the missile fairing doesn't provide sufficient shielding against the radiation from triple ripple? Could it be frying the lasing rod sensors inside the fairing? Or even frying the circuitry that connects to the grav sensor (even if that sensor itself isn't vulnerable to radiation pulses?)
I'm not sure.

I believe wedge geometry pearl.

Jonathan_S wrote:

kzt wrote:Sure, ships can displace themselves inside the wedge. But the job of the missile is to deliver the laser heads and warhead to the the general vicinity of the ship, not to find the ship inside the wedge.

The missile deploys the laser heads and focusing elements multiple seconds out, so at say 500,000 km from the target ship the missile drive shuts down, blows the fairings off the laser heads, warhead and focusing elements and they deploy to attack as they scream by the target at 0.8C.

Since missile grav sensors plus the guidance from the launching ship seem perfectly capable of getting the missile to a trajectory where the payload will pass within 50,000 km of the target, I still don't see how the triple ripple works.

Grav sensors are shown in the laser head drawings, so yes, they have them. The laser heads are what need to find and target the ship inside the sidewalls. Comments by Bu9 suggest that the sidewall is effectively opaque to visible light from the outside and you don't usually have enough time to depend on an active sensor even if radar can penetrate the sidewall (you have something like 30 to 250 milliseconds to against a rolled ship to engage from the point where you can see it past the wedge), so you are pretty much going to have to depend on the grav sensors alone.

[I can certainly see times you would use other sensors, but not so much against active warships.]

Anyhow, given that, what you need to blind are the sensors in the laser heads. However these are inside the missile fairing and hence are not going to be affected by the triple ripple. So their optical, radar, lidar and thermal imaging will also be still working, along with the grav sensor.

Now if you do need some other sensor, then having the missile tubes firing out a set of gigaton yield bombs to go off outside the sidewalls at rapid intervals during the ~500 milliseconds when the laser heads should be in firing range (and looking right at the detonations) would seem likely to rather significantly reduce laser head accuracy.

The laser rods themselves definitely need more accuracy that just knowing where the geometric center of the wedge is; but I can see where the missile itself (before it deploys them) doesn't.

I thought I remembered the sidewall's effect as more like "blurring" the ship's location; not being completely opaque. But I can't find that reference quickly...

I played with some numbers, and even if the ship can only move around within 1% of the 2D area between the wedge planes it's a 0.262 square kilometer needle hiding in an over 450 square kilometer haystack. Random distribution give a single laser rod about a 0.0582% chance of a hit. You'd need hundreds of missiles to statistically expect a hit. So clearly the laser rods manage to aim themselves at the ship (somehow) far more accurately than that.


Maybe the missile fairing doesn't provide sufficient shielding against the radiation from triple ripple? Could it be frying the lasing rod sensors inside the fairing? Or even frying the circuitry that connects to the grav sensor (even if that sensor itself isn't vulnerable to radiation pulses?)
I'm not sure.

kzt wrote:One (ok, two) quick question on the triple ripple: Wouldn't the missiles be primarily using grav sensors anyhow, which should be totally unaffected by a series of really bright flashes? So I could see some loss of accuracy, but with their primary targeting sensor still up they should still be reasonably effective.

If setting off a really bright flash messes up sensors this much, how come ships don't just fire out a set of huge fusion bombs from their missile tubes to go off just as the missile salvo arrives and the laserheads need to lock up their target? They can't look away at that point.

Sensors are electronics, electronics are effected by radiation, even if they don´t seem to get fried, they get shortterm scrambled and possibly taking some longterm damage as well.

Tenshinai wrote:Sensors are electronics, electronics are effected by radiation, even if they don´t seem to get fried, they get shortterm scrambled and possibly taking some longterm damage as well.

Missiles with a wedge up have the same sort of anti-radiation screens as ships do. You also need to get very close, in honorverse terms, to a nuke before things get interesting from TREE and SGEMP. In addition people who get to design weapons carrying nukes usually are at least passingly familiar with the effects of nuclear weapons and make suitable preparations for dealing with this, like using hardened electronics to ensure that missiles don't get killed by fratricide.

For example, a wave of 12,000 missiles doesn't result in 12,000 warheads going off within a ns of each other, they go off as the laser heads decide they have lock and are in range, so you'll have detonations over 100 to 500+ milliseconds. These warheads there are fairly close together, as all 12,000 are inside a sphere about 50,000 km in radius, and don't seem to have any anti-radiation field up. At this point they are subject to x-ray and gamma irradiation from other weapons going off around them and would appear to be maximally vulnerable to radiation damage.

But there doesn't seem to be any significant number of weapons killed by SGEMP/TREE fratricide, so it seems reasonable to assume that they are not very susceptible to radiation damage.

But pods are...

kzt wrote:But there doesn't seem to be any significant number of weapons killed by SGEMP/TREE fratricide, so it seems reasonable to assume that they are not very susceptible to radiation damage.

Zizka missiles were specifically described as extra "dirty", expending much more of their energy into stuff that for a normal missile is useless or detrimental to its intended effect.

But dumps a lot more "bad energy" into anything "looking" at them.

Tenshinai wrote:

kzt wrote:But there doesn't seem to be any significant number of weapons killed by SGEMP/TREE fratricide, so it seems reasonable to assume that they are not very susceptible to radiation damage.

Zizka missiles were specifically described as extra "dirty", expending much more of their energy into stuff that for a normal missile is useless or detrimental to its intended effect.

But dumps a lot more "bad energy" into anything "looking" at them.

Nukes in space emit most of their energy as x-rays, with quite a bit of gamma, visible light is a fairly small proportion. You can optimize somewhat for neutrons, xrays or gamma IIRC. To have lot more visible light produced would take wrapping the bomb in a huge mass of xray absorbent material, like something equal to at least a cubic km of air (which hits the mass limit of missiles). That's about all your options.

X-rays, gamma (and neutrons - at quite close range) are what causes electrical damage, but due to the inverse square law, you have to get VERY close (in honorverse terms) to do anything with nukes in space. Otherwise they wouldn't use laser heads.

"A lot more compared to what? A "lot more" vs 12,000 warheads? A "lot more" compared to 108,000 warheads? Somehow I have my doubts.

Perhaps it's just that the RHN is a lot better at designing radiation hardened electronics, but I tend to doubt it, as there don't seem to be any issues noted with 8th's salvo of 62,000 missile.

Lord Skimper wrote:This is a great question, I would only add the notion some expressed earlier, in the new ship thread, of having a set of short lived wedges that spring up at right angles to the ships wedge. If small enough inside the wedge or if larger, say SD sized outside the wedge.

The missile will have to follow the vector angle but if a new wedge is in the way neither the missile nor the laser head can turn a corner to shoot at a ship. With a temporary wedge extending past the narrow channel of the ships wedge it creates a corner that nothing moving so fast can get around without hit the invicible wedge. Could be the wedge of the keyhole plus a couple ghost rider platform wedges. Only needs be up right when the missiles arrive and given how small the ship is, it only needscover the ship.

Something similar to the practice missile wedge blocking the graser when the sidewall failed in one of the stories in Beginnings.

Why use the CM to kill the missile when it is about to kill itself, just put up an invincible shield until the enemy runs out of missiles.

Long ranges mean the missiles are going so fast contact or wedge hits on the ship are next to impossible. Make the laser heads useless and you are back to a stalemate. Might need sidewall penetrating stealth missiles / torpedoes to kill a ship.

Of course an LAC, if it could get close enough, would be useful again, which is a pretty circular argument for me to make.

Just so that I completely understand, you want a ship to generate a second, short lived wedge 90 degrees offset from the primary wedge. Basically, outside the primary wedge and parallel to the sidewall correct?