penny wrote:I don't know why this is so difficult.
Let's say an LD wins the lottery and finds itself launching from 10 LS away. Theoretically it could be launching from less than half that range. You'd want the missile to launch in that mode even when it lights off.
You want the missile to begin its flight sprinting like Usain Bolt, and not to launch with a leisurely jog then select the kick in mid flight. From 10LS, while in flight, it can be shot down before the mode is selected.
At best you only have 3M km to get that accel up so it won't easily be shot down by point defense. So far so good.
This LD isn't moving at missile speeds past its target ships, otherwise its bow wave could be detected. Let's give it a quarter light-speed relative, 0.25c.
From 3 million km away and with that initial base velocity, a 15-second million-gravity acceleration will bring the missiles up to 0.75c, which is good because that high speed makes interception difficult. But the missile will only have crossed 5.5 light-seconds, so it would coast for 4.5.
The missile has to last a bit longer to cross the full distance, or be launched closer. It needs to last 21.5 seconds at a million gravities for a 3-million-km run.
Nothing we've seen so far indicates this acceleration is possible for any period of time, let alone 15-20 seconds.
In 20 seconds, the quarter-light-moving LD will close to half the dsitance to the targets. This is not enough for energy weapons... but is for CMs and shipkillers. Even if the defenders can't clear quickly enough to fire shipkillers, they may be able to fire CMs. Any CM that didn't target the incoming million-gravity missile can go after the launching ship, which was locked on.
In the 40 seconds it has, the LD can only deflect a measly 2000 km. That means it will be flying into debris, or will be within gun range of any ship that survived and turned wedge.
That actually means the LD would never be flying at quarter-light straight towards the targets. It would need to fly at a tangential course, which means the initial velocity vector for the missiles isn't pointed towards the targets and instead they'd need a parabolic course that I'm not in the mood to calculate right now...
Necessity is the mother of invention, and no other navy expected to be launching from such close ranges. Heck, energy range? You can see a wedge coming. You can't see a spider crawling until it is too late. So a spider has a reason to develop such a missile. Wedge based ships never had a reason to consider premature ejaculating missiles. And the certainly never had a chance to employ them.
You mean "luxury," not necessity. The LDs don't need to be at those insane close ranges. Though I will point out that 3 million km was regular range maybe half a century ago.
"Necessity" would be if they had these ships that could not win from anywhere and they had to come up with at least one winning strategy. I don't think this is likely, because a) there's a huge chance of not winning anyway (see above) and b) the ships wouldn't be designed in the first place without a possible winning strategy in the first place.
As for wedges not having a chance... the LACs during their first battle were stealth enough. It was because the PN didn't know what they were seeing, but it did allow them to close to energy range. And yet the RMN didn't invent the million-gravity missile.