Demarquis wrote: ↑Tue Feb 15, 2022 6:28 pm
@Bamax:
"And regarding real world space lasers, unless the focusing lens itself is gigantic, it's effective range won't be all that great.
Which means that a giant laser is nigh unlikely to stop the equivalent of a freight train (a giant missile) from crashing into it and destroying it."
Er, that depends. First, why can't the focusing lens be "gigantic", whatever that is taken to mean? Second, many smaller lasers can combine their beams on the same target, increasing the energy they transfer and also their range. Third, it's possible to mission kill the missile without necessarily vaporizing it: destroying the sensor package, the warhead, or the maneuvering thrusters alone would be enough.
@Gaerzi: "The spaceship also needs sensors, flight computers, engines, and fuel, but it also needs more stuff. Like the jump drive and crew quarters and life support systems. Also the space ship is not consumable. You don't want to lose it forever in deep space just because the engine fizzed out. Whereas if you lose a missile, well, it's too bad it didn't go and blow up an enemy ship but you were planning on losing it anyway. So your spaceship will have redundancy everywhere, and the best systems you can get. So that makes it that the minimum size of a spaceship is probably larger than the minimum size of a missile.
There's really one factor that can make or break the "bigger missiles than ships" and it's the size of the fuel tanks. The missiles need enough fuel to cover engagement range (including maneuvering) and keep enough surplus fuel to serve as an effective payload (unless they're carrying a dedicated explosive payload). The spaceship needs enough fuel to cover cruising range while carrying the missiles. Most likely, cruising range will be superior to engagement range, otherwise you may as well use static defenses."
I largely agree with your first paragraph, disagree with the second. Of the things you list as necessary for a ship but not a missile, the most important is the human crew and all the associated equipment and supplies. This leads us to the question: "Why do combat ship in the Outsider universe require an organic crew?" Evidently, and by authorial fiat, organic critters add some sort of advantage that AI cannot match. Fair enough. In that case, it makes sense for ship designs to cater to the needs of the crew, while missiles can dispense with all that. In other settings, this might not be so true. In real life, it almost certainly won't be true.
I think you make an error in the second paragraph, however, by conflating range with delta-v (ie, "change in velocity", or acceleration). The missiles need enough fuel (propellant) to match their target's evasive maneuvers and still have enough mass and/or relative velocity left over to do significant damage (the more of a velocity advantage the missile has over the target, the less mass it needs to do the same mount of damage). Meanwhile, "cruising" requires no more delta-v than is needed to accelerate to the desired velocity, and from there the ship can coast without using any fuel at all, unless it needs to correct its' course for some reason. Whether the ship needs more delta-v to complete its' patrol or the missiles need more to catch the target (which will frequently be an enemy ship cruising on its' patrol) will depend on specific circumstances. I can even see a trade-off where the launching ship's delta-v could be maximized at the expense of the missiles, or the reverse, depending on the mission. This is where using missiles as a back-up source of thrust might come in useful.
I would suppose that in general, to the extent that the target's point defenses are strong (whatever form that takes in a given setting), the less of an advantage delta-v will be for the ship, and the more advantage it will be to give it over to the missiles. This is because the missiles will need that delta-v in order to evade the point defenses and catch the targets (this may take the form of a large number of small missiles which nevertheless add up to a significant amount of the total delta-v). On the other hand, to the extent that the enemy's point defenses are weak, the more advantage will be derived from putting that delta-v into the launching ship's main drive, because getting within range and acquiring an advantageous launching position will be the main challenges (this may take the form of a small number of relatively larger missiles which add up to a reduced fraction of total delta-v).
As you can see, the number of missiles, and the size of the missiles, is a trade-off that complicates the issue. The real underlying question is where the delta-v budget is to be spent: is it to be made available mostly to the missile drives, or to the ship's drive?
"Small ship/large missile" is a design that will likely be most advantageous when in a positional disadvantage against an enemy ship larger and more capable than one's own (because giving the missile as much delta-v as possible is the only chance of hitting it). If humans were to go up against the Loroi, they would be well advised to deploy very large missiles in the hope that the wreckage will manage to intersect the enemy despite their advantage in point defenses (actually, I would advise them to develop an FTL missile, and start lobbing across the lightyears).
"Large ship/small missile" sounds to me more likely when in a positional advantage with better ships than the enemy has. Maneuver circles around them, and pick them off with cheap missiles. This is the Loroi against the humans (they need to get into human inhabited space as soon as possible to force the enemy to engage with their inferior vessels).
But really, the underlying question is still where should the delta-v go within the "ship-missile system"? Do you invest primarily in the ship, or in the missiles (bear in mind that the ship must carry the missiles until they are fired)? And what are the consequences of making a mistake? Again, this is where having some options (such as converting the missiles into back-up thrusters) might be helpful.
