6g doesn't matter. Not true, it matters, but not enough.
If ships are even sort of realistic in a way we expect, the 6g thrust is out the back, right? Traveller ships have big, cool m-drives at the back, right? Else they are UFOs and can instantly go 6g in any direction. So to evade at 6 g, the ship has to be pointed at a right angle to the intercept vector for maximum deflection relative to the missile.
We will assume this is always the case, while in reality, the ship first has to rotate to that position, and this means it might have to chose which missile (or group) it will try to evade maximally. (this has some great role-playing implications, BTW, you evade vs one, and decide to shoot at the other, for example)
In 1 second, at 6g, a ship is displaced 29.4 meters. That's it. That's what 6g bought you, ~30m. If the ship is bigger than 30m, and the missile was gonna hit when it was 1 second away, it's still gonna hit. Note that for our 6g missile, that 1 second is several hundred km away at t=0 (where t=1 is impact). ...
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Scale. Don't forget scale. Anything from 10 thousand kilometers to a light-second or more. Turn lengths of a thousand seconds to 20 minutes.
If you and I are matching course and speed at those ranges, trading shots, and I see a missile emerge from your locus, I do not have 1 second to react; I have many minutes. Turning is only a tiny fraction of that. I put my butt to you, thrust away from the missile, the missile has had only seconds to accelerate before I respond. At that point it's a math exercise: can a missile accelerating "upstream" catch a ship that's accelerating away from it? Key variables: the missile's thrust, the missile's initial velocity with respect to the ship, the ship's thrust, the distance between them, the amount of fuel the missile has. At those ranges, it is pretty much impossible for a 6G missile to catch a 6G ship from behind before running out of fuel, given only the few seconds between launch and the time the target completes its turn and lays on thrust. Lower acceleration, depends on just how far off the target is and how much fuel the missile has, but it's very much like dealing with torpedoes - the farther off he is and the more power he has, the harder it is to catch him.
If I'm pursuing you when you launch a missile down at me, basically same problem. If you are pursuing me and launch missiles, basically same problem except I don't spend a few seconds turning. The missile starts life with your velocity, so everything's relative to the numbers between us, not the absolute numbers. A 6G missile's best chance is against an opponent of 5G or less; at 10,000 or more kilometers,
unless there's a fairly decent velocity difference between the two ships - in the missile's favor - there's no chance if the 6G target reacts to a 6G missile immediately.
Look at it in terms of Book-2 turn sequence:
lntruder Player Turn
A. Intruder movement: "The intruder moves his ships using the movement, gravity, and other applicable rules. Ordnance (missiles and sand) which he has launched in previous game turns is moved at the same time."
...
D. Intruder ordnance launch: "The intruder may launch ordnance (missiles and/or sand) at enemy targets ... Ordnance which has contacted enemy ships explodes in this phase."
Native Player Turn
A. Native movement: "The native moves his ships using the movement, gravity, and other applicable rules. Ordnance (missiles and sand) which he has launched in previous game turns is moved at the same time."
...
D. Native ordnance launch: "The native may launch ordnance (missiles and/or sand) at enemy targets ... Ordnance which has contacted enemy ships explodes in this phase."
And then back to the beginning.
The native moves after the missile is in space but before the missile moves. If the native can get out of the missile's one-turn range with that movement, the missile does not impact that turn. If the native can keep adding up vectors to stay ahead of the accelerating missile, the missile never hits. And, that's much easier if you have the same thrust as the missile; you've got to be doing something pretty stupid or pretty daring - closing range fast and unable to kill that vector quickly enough - to get hit.
Realistically speaking, things don't happen in 20-minute increments and 10-thousand kilometer hexes. In "real life", so to speak, there's a window where the target's close enough that the time it takes for the ship to turn and react gives the 6G missile has a chance at connecting - if the target is really, really close. However, the intercept velocity at that point is low.
In a word, 6G missiles suck rocks against 6G ships at anything beyond the space equivalent of "point blank" range or unless the 6G attacker's making himself vulnerable, something that High Guard doesn't seem to notice. Unfortunately, correcting this within the game parameters is difficult 'cause even a 7G KKV interceptor can thwack a 6G ship a lot harder than any ol' 30-kilo warhead can, given adequate time to build up speed, and it can do many, many times worse to the poor 1G crawler. You'd basically need to scrap the rules and come up with a damage system that more accurately reflected the impact differences between chasing down a 1G ship and chasing down a 6G ship.
