Graser replacement

kzt wrote:

Timeonit wrote:Can anyone tell me how this is handled in the Honorverse, or are the energy ranges low enough that even if you miss you don't have to worry about anything behind the target?

An actual multi-meter gamma ray laser would be deadly to a horoverse warship out to at least light hours, possibly deadly to soft target out to light months or beyond. The beam would be something like twice as large at a few light hours than it is a light second. It's unclear how the honorverse grasers work.

That is only true if the beam is really well collimated. That might not be true for grasers, since it is possible (likely?) that they cannot be internally reflected before emission. If grasers are not well collimated, they could diverge far faster than you are assuming.

Timeonit wrote:Okay,
thank you for the fast answers and clarifications.

One thing the rest of the group didn't mention is that the distance Honorverse ships are from each other makes hitting another ship in formation close to impossible.

The sidewalls and wedge tend to block sensors and make it difficult to see exactly where a ship is relative to it's wedge - there is a relative relationship between the wedge and the ship's location, but there is a little slack in the ship's placement from optimization to hide it from weqapons attack.

So, on an SD, the Broadside area between the wedges is about the area of New York State (give or take a little). The fuzzy area the ship is most probably in is somewhere between the size of Manhattan island and the size of NY's Central Park (depending on the quality of your sensors). The Ship itself has a broadside of about 1/25 the area of NY's Central Park (or say, just Central park between 59th and 61st streets).

And you are trying to hit this target with a laser beam the size of a sm passerger car or a graser the size of a delivery van from 3x the distance from Earth to the Moon (at max range).

In parking orbits, ships usually keep 5000 KM between them to allow the wedges to come up safely - or roughly the width of lower 48 United States. Even at close, wedge bumping distances, 2 SDs would be >600 KM apart

In short, there is lots of space between ships in Honorverse formations - the chances of a laser missing a ship (and not being totally distorted by 2 passes through the target ships's sidewalls) and accidentially hitting another ship traveling in formation (and still having damaging power after the 3rd sidewall transit) is incrediably slim.

SWM wrote:

KNick wrote:A point to remember about Honorverse KEWs. They are already single stage, variable acceleration, capacitor powered missiles with very precise controls. They are very short range and very accurate. Are you suggesting using these types of KEWs?

No, the KEWs that people were promoting were unpowered devices (except perhaps for terminal adjustment) which were to be accelerated by the launching ship. Which we have shown is not plausible in the Honorverse.

Nor plausible?

Honorverse tech can build a gravity generator that produces a 3eex7m/s per meter gradient that is intense enough to contain a nuclear explosion.

This suggests that near lightspeed particlecannon can be only 100 meters long and gravity cannon for heavier, more complex projectilex (bomb pumped x-Ray lasers) could be only 1 km long.

"Pulsars" in the honorverse are small arms that can accelerate projectiles to hypersonic velocities within a few centimeters.

This technology is very plausible.

namelessfly wrote:

SWM wrote:No, the KEWs that people were promoting were unpowered devices (except perhaps for terminal adjustment) which were to be accelerated by the launching ship. Which we have shown is not plausible in the Honorverse.

Nor plausible?

Honorverse tech can build a gravity generator that produces a 3eex7m/s per meter gradient that is intense enough to contain a nuclear explosion.

This suggests that near lightspeed particlecannon can be only 100 meters long and gravity cannon for heavier, more complex projectilex (bomb pumped x-Ray lasers) could be only 1 km long.

"Pulsars" in the honorverse are small arms that can accelerate projectiles to hypersonic velocities within a few centimeters.

This technology is very plausible.

Check your math. Even at 3e7 m/s^2, it takes well over a kilometer to get close to light-speed.

I assume you are referring to the gradient in an impeller wedge? You should remember several things about impeller wedges. 1) They are not produced by the same kind of gravitics as tractors and launch tubes. 2) Even the entire output of a ship is not sufficient to run an impeller without drawing almost all it's power directly from the spatial medium.

If relativistic gravitic railguns were plausible, don't you think missiles would be launched from the broadside with a lot higher velocity than they are? There is no evidence that the Honorverse has gravitic accelerators capable of anywhere near the acceleration necessary for it on a ship-borne weapon.

Do we have any text examples that state the initial velocity from broadside tubes.

Perhaps I did not properely state my assumptions.

I was not stating that the gravitational field in an Honorverse fusion reactor imparted an accelleration of 3eex7m/s^2

I was stating that the gravitational field was intense enough to create a gravity well intense enough that the potential energy over one meter was equivalent to a delta vee of 3eex7 m/s.

This implies an average gravitational field of 9eex14m/s^2

The gravity focusing array for laser heads would need to have a similar gradient.

This might seem to be absurd, but it is the performance needed for a Mk-16 fusion bottle.

Come to think of it, this is the potential energy gradient of contemporary, real world "fusion reactors" (aka welfare for plasma physicists).

Also remember that Honorverse gravity lenses bend light as do sidewall generators.

Skimper's gravity gun idea is entirely consistent with Honorverse technology.

It would also have the advantage that the projectiles are invisible to granitic sensors so they will have little risk of interception.

SWM wrote:
Check your math. Even at 3e7 m/s^2, it takes well over a kilometer to get close to light-speed.

I assume you are referring to the gradient in an impeller wedge? You should remember several things about impeller wedges. 1) They are not produced by the same kind of gravitics as tractors and launch tubes. 2) Even the entire output of a ship is not sufficient to run an impeller without drawing almost all it's power directly from the spatial medium.

If relativistic gravitic railguns were plausible, don't you think missiles would be launched from the broadside with a lot higher velocity than they are? There is no evidence that the Honorverse has gravitic accelerators capable of anywhere near the acceleration necessary for it on a ship-borne weapon.

namelessfly wrote:Do we have any text examples that state the initial velocity from broadside tubes.

Not that I can think of. Short Victorious War probably had the best description in the infodump on the pods; but it didn't give any specifics.

Short Victorious War wrote:The old pods' launchers had lacked the powerful mass-drivers which gave warships' missiles their initial impetus. That, in turn, gave them a lower initial velocity, and since their missiles had exactly the same drives as any other missile, they couldn't make up the velocity differential unless the ship-launched birds were stepped down to less than optimal power settings. If you didn't step your shipboard missiles down, you lost much of the saturation effect because the velocity discrepancy effectively split your launch into two separate salvos. Yet if you did step them down, the slower speed of your entire launch not only gave the enemy more time to evade and adjust his ECM, but also gave his active defenses extra tracking and engagement time.

That gives the impression that the difference is significant, even in a missile that's capable of reaching around 76,000 KPS in 180 seconds. [I'm number crunching with OBS era single-drive missiles, 43,000g at their 50% power max-range settings]

Playing around with the numbers though, that seems improbable.

Even if you give the mass driver the seemingly ludicrous ability to impart 1,000,000 m/s velocity; at 6.8 Mkm the ship launched missiles only get there about 2.35 seconds sooner. Alternatively you'd need to step down the ship-launched missiles by about 1,140 g (to 41,865g) to achieve time on target with pod launched missiles. Compared to what the shipboard missiles would do, with that high initial velocity and 50% power (43,000g), they'd now have 2.6% lower terminal velocity, the pod based missiles only 1.3% lower terminal velocity. (That's giving the pod launched missiles no initial velocity and 50% power)


Doesn't seem like a significant difference, from even a quite high initial velocity.

namelessfly wrote:Perhaps I did not properely state my assumptions.

I was not stating that the gravitational field in an Honorverse fusion reactor imparted an accelleration of 3eex7m/s^2

I was stating that the gravitational field was intense enough to create a gravity well intense enough that the potential energy over one meter was equivalent to a delta vee of 3eex7 m/s.

Where do you get that figure?

It is a reasonable inference from basic fusion reactor physics.

The gravity containment system has to not only contain the hot plasma but the fusion reactor products.

I am assuming that the reactor plasma is not large enough and dense enough for the fusion reaction products to be thermalized to the lower average energy before reaching the reactor vessel walls. Since even the "clean" fusion reactor fuels (whose fusion reaction cross sections are small relative to D-T and D-D retains and thus their power density sucks) have sideband reactions that produce Neutrons, your reactor containment field needs to create a deep enough gravity well to shield the reactor walls. If not your missile will transform itself into radioactive slag.

This assumption is validated by the gravity focusing of fusion explosions in laser heads. Even if the fuel burn fraction of the explosive device is on the order of only 10%, you still getba plasma with a characteristic velocity of 1eex7 m/s. It takes a very steep gravity well to contain that.

SWM wrote:

namelessfly wrote:Perhaps I did not properely state my assumptions.

I was not stating that the gravitational field in an Honorverse fusion reactor imparted an accelleration of 3eex7m/s^2

I was stating that the gravitational field was intense enough to create a gravity well intense enough that the potential energy over one meter was equivalent to a delta vee of 3eex7 m/s.

Where do you get that figure?

SWM wrote:

kzt wrote:An actual multi-meter gamma ray laser would be deadly to a horoverse warship out to at least light hours, possibly deadly to soft target out to light months or beyond. The beam would be something like twice as large at a few light hours than it is a light second. It's unclear how the honorverse grasers work.

That is only true if the beam is really well collimated. That might not be true for grasers, since it is possible (likely?) that they cannot be internally reflected before emission. If grasers are not well collimated, they could diverge far faster than you are assuming.

This is why phased array graser technology might be a profound improvement n Graser technology. Given the SLN huge investment in energy armament heavy SDs, this is a technology that the SLN might have pursued.