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Max ship speed?

I was fully aware that we do that, they did this from a NASA/university office complex that my mother worked at in the 1970s.

BIG difference between a little laser bouncing a ranging shot, and Traveller lasers delivering enough joules to punch through our ship hulls and damage/destroy systems with no effective attenuation across 250,000km.

Only in the size of the apparatus. The accuracy is the important bit. That, and the focus.
 
lasers/energy weapons

to my mind the problem with lasers is the target won't be where your sensors say it was and if the ship is moving very fast and jinking then the cone it could be in will be huge so I don't see one laser hitting a target like that being very likely.

on the other hand I can see multiple lasers fired together as a battery to create a criss cross pattern across the space the target might be in might work - like a laser shotgun effect?

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missiles

for the reasons mentioned above i have a hard time picturing standard traveller missiles as anything other than short range because of the fuel requirement against an evading target.

an alternative I can imagine is massive torpedoes which are effectively the same as small craft which can chase a target with it's own sensors and evade program - sort of like ramming with a shuttle.

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sand

if it's correct that when you combine a fast moving target making small jinking moves with the time it takes for your sensor to say where the target was that you get a very large cone of space where the target might be when you fire then sand sounds like it might be very effective - relatively speaking. It's effectively canister or shrapnel except relying more on the target's own speed to cause the damage.

so move slow and get hit by lasers, move too fast for lasers and you become vulnerable to sand.
 
Well, the same issue with lasers and missiles also applies to sand--once you get to the potential area in which a ship might be, you are tasked with getting a huge amount of sand dispersed across a huge amount of space. You can probably make more lethal sand pellets than you can shotguns of laser effect, but it is approaching at sub-light, and thus must effect a much more huge potential-area-in -which-opposing-ship-might-be.
 
lasers/energy weapons

to my mind the problem with lasers is the target won't be where your sensors say it was and if the ship is moving very fast and jinking then the cone it could be in will be huge so I don't see one laser hitting a target like that being very likely.

I disagree. While the lunar laser distance experiments are I believe (and I think Aramis agrees) of little or no probative value here, and we can only guess about the actual trajectory of computing power ( ;) ) as well as the actual effects of such, physics will still be physics.

Well, when you think about acceleration/size, and the relative distances involved it is physically feasible.

At the maximum range in CT for starship combat, 2 light seconds, IIRC, it takes the image 2 seconds to get there, and the laser 2 seconds to get back. If we assume 1 seconds for the computer to process the image and execute a firing solution, the shot takes 5 seconds. Without considering the recharge time, if any, there could be one shot every 5 seconds. In a 1000 second turn, thus up to 200 shots are conceivable.

If we have a 100 meter starship, which at 1G can only change its vector a maximum of 50 m/s (and thus change its relative position 125 m) in that time-frame, it is certainly feasible that one of those 200 shots will hit it.

A more realistic example is the Kinunir, at about 80 m long, and about 40 m wide, going out at 4G (I forget its agility, but we will assume it is 4). At its maximum profile, then, it presents a cross-section of 3,200 m^2. At its maximum acceleration, simplistically, it could change its relative position by 500 m, which would be greatest from the perspective of the shooter when in the plane at right angles to the gun-target line. Thus, the target's profile would be, from the shooter's perspective, somewhere within this 250,000*pi m^2 area. I get 245 shots to cover the whole area.

This is, of course, simplistic: smaller cross-section (and less movement relative from the shooter's perspective) at different aspects. It costs time, thus acceleration, to flip the ship, so the "circle" would be more elliptical.


Make it an AHL, with comparable acceleration, and a much huger cross-section, the equation becomes more favorable. Rampart, almost impossible without varying assumptions (less powerful shots in groups?). Shorten the range, and everything becomes easier, of course. What will recharge time, and actual computing power do? Well, we can only guess. The point is, it is physically feasible to achieve a hit, given what we know, and assuming favorable enough outcomes for what we cannot predict.

missiles

for the reasons mentioned above i have a hard time picturing standard traveller missiles as anything other than short range because of the fuel requirement against an evading target.

I actually think this is easier. Power to get to the target, and while in proximity of the target, with much higher acceleration, the missile is much more maneuverable. The "corrections" are minimal until in very close proximity.

Our fighters could out-maneuver identified SAMs in Vietnam because although the missiles had higher acceleration, and speed, they had less ability to pull lateral-G's to change direction, because of much smaller control surfaces. In vacuum, it's all thrusters (and gimballed drives, presumably) to spin, and drives to shift laterally. The higher-G motor, with a quicker "spin" from thrusters and lower turning moment, will be more maneuverable. At the last moments, a ship's possible maneuvers become limited by its attitude, rotational velocity, and maneuver capability. I say the missile's got a very good shot, at least from the point of view of what's physically feasible.
 
I disagree. While the lunar laser distance experiments are I believe (and I think Aramis agrees) of little or no probative value here, and we can only guess about the actual trajectory of computing power ( ;) ) as well as the actual effects of such, physics will still be physics.

I do not agree. The spot size on the moon for some of the DME is only abut 500m. That we can accurately point hubble to fractional arc seconds accuracy also is probative.

We routinely put highly accurate optical solutions in place.
We have an in-atmosphere laser system of 150 kW able to hit missiles destructively at over a km at present; it penetrates hull steel at that range, and is 1/1666 the power, so (given the inverse square law alone) should be 40km in atmosphere. Out of atmosphere, we should be able to collimate the beam better and not suffer atmospheric diffraction and absorption.

You missile should have to overwhelm the lasers to even get close. And, given the small surface area, it's not escaping the beam and not losing heat fast enough to avoid thermal shock issues, even if it's not instantly destroyed.
 
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If we have a 100 meter starship, which at 1G can only change its vector a maximum of 50 m/s (and thus change its relative position 125 m) in that time-frame, it is certainly feasible that one of those 200 shots will hit it.

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I see your point with 200 shots in a combat round.
 
I see your point with 200 shots in a combat round.

Well, I'm not saying all the math works, but that it's in the realm of the feasible. Specifically, I have not taken the time to figure out how the size DM's of HG2 really track with the actual areas involved. Way too many variables before bed...
 
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