Graser replacement

Commodore Oakius wrote:I follow all your logics, and I agree. But I have another question: has it ever been discussed about the power requirements needed to fire a grazer, or lazer, continueously for, say, 10 seconds? This would allow limited tracking capability, presuming the mounts was capable of moving to do the tracking.

MaxxQ wrote:Not possible. Unless you use the graser torpedo from the MAlign, and then it self-destructs due to overloading. Shipboard grasers are fed power from capacitors, which release their energy in a single burst, then need to be recharged.

Jonathan_S wrote:First (from the bit I snipped), you remembered the Mk13/Viper accel correctly. AAC, ch 19 confirmed it's 130,000g for 75 sec.

Second even if you could step down the power or otherwise lengthen the firing time of an energy mount it wouldn't really help for tracking. At energy range you're over half a light-second away. So you're already having to lead the ship and fire where you think it'll be. Attempting to correct a continous beam based on how far wide it missed means you're making a correction based on 0.5+ sec old data to attempt to hit in another 0.5+ seconds.

That might tell you if your emitter was somehow misaligned, so you aren't hitting the point in space you were targeting. But it does nothing to help you know exactly which point in space their ship will be in another half-second from now. (And assuming your sensors or remote platforms are use to seeing how far you missed your aim point I'm not sure why they'd have an easier time doing that to a continuous beam that's waving around rather than a pulsed burst)

(Stupid nested quote rule. . . [grumble, grumble, grumble] What idiot designed this site?! I mean ---- What? Oh. Oh, yeah, that's right. Forget I said anything. )

In fairness, and while all the reasons which have been adduced for why you can't generate very long "bursts" from weapons as powerful as grasers in the HV are completely correct, the ability to do so (if possible) would have some advantages for fire control. In essence, it would let you create a larger version of what the USN called the "danger zone" for BB gunnery. If you have a projected volume in which your target might be, the ability to sweep clear across that volume (or a largish chunk of it) with a single shot would increase your chance of scoring a hit as opposed to using a weapon which can target only a single point within that volume.

The notion of doing that with a KEW is fairly ludicrous, however, and using a weapon even 10% lower than the speed of light will cause a decrease in hit probability vis-à-vis a beam weapon unless the KEW has the ability to maneuver to track its target. This is, essentially, the description of a missile except that laserheads have the ability to engage targets at range without needing to score a direct hit.

And the notion that even HV tech could accelerate to "near light-speed" in any conceivable internally or pod-mounted launcher is . . . ill conceived, to say the very least. If the HV did go for ship-to-ship kinetic weapons, they would indeed have to be an adaptation of existing missile as Weird Harold has suggested. The problems in getting through the defensive zone and actually hitting the target would remain, but it would at least let you accelerate to higher cee-fractional speeds . . . depending on the range. And, of course, the longer the range (and hence the acceleration time), the poorer the firing solution at launch.

There's a reason I use KEWs for planetary combat and against very short-range targets in space but not at anything approaching normal fleet combat ranges or true cee-fractional velocities.

Did someone say "danger zone?"





(Sorry, I just like Archer a lot. Back to your regularly scheduled programming.)

MaxxQ wrote:

munroburton wrote:The highest acceleration record in the Honorverse hasn't exceeded 100,000g yet. No warhead available is going to survive the huge accelerations implied by such a weapon.

Minor nit: IIRC, the Viper and Mk31 CMs hit 130,000 g's at max setting. Just going by memory, but I definitely recall *something* hitting that number.

D'oh. I was thinking of the MK23's 92(or was it 96?) thousand gees.

Well, an error of ~40,000 isn't much considering the size of the other numbers in my previous post.

munroburton wrote:

MaxxQ wrote:Minor nit: IIRC, the Viper and Mk31 CMs hit 130,000 g's at max setting. Just going by memory, but I definitely recall *something* hitting that number.

D'oh. I was thinking of the MK23's 92(or was it 96?) thousand gees.

Well, an error of ~40,000 isn't much considering the size of the other numbers in my previous post.

Oh, I know it doesn't matter to the point you were making... I just wanted to be nitpicky about one particular number.

Also do we know how a sidewall would effect a KEW? If memory serves a sidewall involves gravitic distortions of some kind. That sounds like it would have massive negative effects on a KEW's damage potential and accuracy unless they add sidewall penetrators to every bullet.

Roguevictory wrote:Also do we know how a sidewall would effect a KEW? If memory serves a sidewall involves gravitic distortions of some kind. That sounds like it would have massive negative effects on a KEW's damage potential and accuracy unless they add sidewall penetrators to every bullet.

I figure that if the grav gradient is high enough to bend light (lasers and grasers), then it's surely high enough to pretty much destroy anything physical (unless using penaids, as you mentioned). It's mentioned quite often in battle scenes that incoming energy fire, whether from shipboard grasers/lasers, or x-ray lasers from missile laserheads, get bent and/or weakened by the sidewalls.

I suspect that most of those that miss are due to impacting the sidewall at some angle or other - the ones that make it through to cause damage probably hit more or less perpendicular to the sidewall*. Another possibility is that those deflected/bent beams were going to miss anyway, had there been *no* sidewall, and the bending of the incoming fire actually bent it in a direction to hit the ship and cause damage.

*Kinda like how the Wolter mirrors work for the lasing rod on the laserhead - x-rays normally go through the mirror material when they hit it at a little beyond parallel up through perpendicular, but at *very* shallow angles (like those you would get from detonating a warhead aft of the laserheads) the Wolter mirrors actually deflect/reflect the x-rays into the lasing rod.

http://en.wikipedia.org/wiki/Neutron_mi ... ter_mirror

The idea appears to be a slug of metal, not a warhead.
However, the aim issue is the same for a graser as for a slug, except you could defocus the graser to hit a broader area.

munroburton wrote:According to http://en.wikipedia.org/wiki/Relativistic_kill_vehicle, "to reach 1% of light speed over the length of a one-meter accelerator would require 4.5 * 10^12 m/s^2 (or over 450 billion g) of acceleration."

Ok, call it a 10 metre long accelerator: 1% of lightspeed would still need 45,000,000,000g of acceleration. Ok, let's go to the stupid waste of resources example: Using the 1395 metre length(of the HV's longest warship) as an accelerator: 322,580,645g.

1% of light speed. Assuming .9c is the objective, the SD-length accelerator would need "only" 29,032,258,064g of acceleration. For the ten-metre accelerator, 4.05 trillion gravities of acceleration is required.

The highest acceleration record in the Honorverse hasn't exceeded 100,000g yet. No warhead available is going to survive the huge accelerations implied by such a weapon.

Accuracy is also going to be problematic. The graser's maximum effective range is limited because targets under full power can make all sorts of evasive maneuvers, never mind simply rolling their wedge. The further away they are, the earlier you are going to have to predict their movements and using a cee-fractional weapon instead of a lightspeed weapon will only shrink that effective range, producing an inferior result.

MaxxQ wrote:

I figure that if the grav gradient is high enough to bend light (lasers and grasers), then it's surely high enough to pretty much destroy anything physical (unless using penaids, as you mentioned). It's mentioned quite often in battle scenes that incoming energy fire, whether from shipboard grasers/lasers, or x-ray lasers from missile laserheads, get bent and/or weakened by the sidewalls.

I suspect that most of those that miss are due to impacting the sidewall at some angle or other - the ones that make it through to cause damage probably hit more or less perpendicular to the sidewall*. Another possibility is that those deflected/bent beams were going to miss anyway, had there been *no* sidewall, and the bending of the incoming fire actually bent it in a direction to hit the ship and cause damage.

*Kinda like how the Wolter mirrors work for the lasing rod on the laserhead - x-rays normally go through the mirror material when they hit it at a little beyond parallel up through perpendicular, but at *very* shallow angles (like those you would get from detonating a warhead aft of the laserheads) the Wolter mirrors actually deflect/reflect the x-rays into the lasing rod.

http://en.wikipedia.org/wiki/Neutron_mi ... ter_mirror

What I am thinking about with respect to hypervelocity "slugs" is their use against Spider Drive ships. With their extreme stealth, it may be possible to localize Spider drive ships but not to acquire sufficient return from LIDAR to attack them with laser heads. In that case, using an area weapon of 1 kg slugs carried as payload on a standard missile could disperse over a wide area, and the impact of a single slug would release similar energy to a 1 MTon blast. This obviously presumes that Spider-drive ships do not have sidewalls or other deflection technology. I doubt that a PDC would have a good chance of hitting a 1 kg slug at relativistic speeds.

An analogy might be the WW II Hedgehog ASW weapon.

-- Bob G

1. Any physical object that hits a sidewall will get ripped to atoms. Useless against impeller-drive ships unless you get it up kilt/down throat, in which case the graser would be better.

2. Using them as canister shot against spider-drive ships has possibilities. At least you can present the spider ship with a real pickle: hope to not get hit by dumb luck, or raise a sidewall that shows up on gravitic sensors. A moderate salvo of missiles could deliver an awful lot of 1 or 2 kilogram projectiles.

[afterthought: if each missile tracked its projectiles, and noted the exact location of any that mysteriously disappeared, it could generate a pretty good fix on the spider-sneak even if it didn't do any damage]

Had a thought about The Stars At War - instead of using whole fortified asteroids, break each one up into a few billion 10 to 20 kilogram chunks and shoot them all at the Bug planet at 20% C or so on different vectors. I don't care how many Bugs and how many gunboats, they can only stop a tiny fraction of that.
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At my house, the "things that go bump in the night" are called cats.

The cluster warhead.

Might not this work on missiles as well?

As you all know I'm no physicist, I figured a gigawatt laser must use a lot of power, enough to power a country at current era for a while?

Given we can accelerate with a rail or guass gun a projectile to 8kms now, in 2000+ years making it go 100,000 times that shouldn't be out of the question. Just requires power.

Also couldn't the wedge just spit the projectile out at near light speed? Plus the build up would be, for a SD 280+km.

Also it depends how fast the enemy ship is going, if they are going 0.3c and you are going 0.2c you only need 0.5c any more wouldn't make any difference. Can't go faster than 1c.

Didn't consider sidewalls. Do ships flying into a system jig and jog or just fly in throat wide open? Jigging and jogging would slow them down, no?

I always read the books as having them come blazing right in.

I can see a slug that isn't right in front of a ship having an even harder time avoiding a sidewall, a slight angle off and the sidewall kills the idea. Unless you use a laser head or have this as an aft firing chase launcher, while running away. Some kind of wedge accelerated KEW launcher on a freighter might give a pirate second thoughts.