Demarquis wrote: ↑Fri May 27, 2022 12:50 am
If the space fighter and the larger carrier ship are using the same drive design, then the fighter is just a carrier scaled down, and the carrier is just a very large fighter.
They're
not the same design, though. While they may both utilize the same
underlying technology, there are still significant engineering challenges involved in
applying that technology that are sensitive to economies of scale, and multiple engineering trade-offs that can be adjusted to favor one dimension of performance over another. For instance, the powerplants of WWII era destroyers were optimized for speed over all. Battleship propulsion plants also used the same underlying steam-turbine technology, and they even pushed for high power outputs (thus enabling the "fast battleship,") but were nowhere near as fuel-hungry as their smaller escorts. Not just in terms of consumption to available on-board fuel tankage, but also in pound-for-pound terms - efficiency was sacrificed for raw power output from a small, dense powerplant.
Another excellent example of this is an airliner's jet-turbine engine compared to a fighter jet. The commercial engine only needs to achieve a peak power-to-weight ratio sufficient to move an airliner at most optimal cruising speed, while the fighter engine needs to be capable of significantly more peak output, even if it cruises at the same speeds. And then there's the afterburner system - a case study in sacrificing fuel efficiency for short-term performance. It's technically an oversimplification to say that it's a rocket-boost system for a turbine engine, but it's more than accurate to characterize the power output and the fearsome fuel consumption that it costs. There's also other aspects of performance to consider - for instance, durability and maintenance demands. Military requirements make life difficult because they need all these aspects at the same time - high performance in combat, efficiency and durability out of combat to enable long patrols - but the engineering requirements for each are almost always mutually exclusive. This strongly incentivizes splitting your sustainment mass and combat mass - put efficient, durable engines on the carrier, and fuel-hungry but high-performance engines on your fighters. (Note that this applies to full-size warships, too, not just fighters - tugs/tenders that use external docking collars to tow Fast Attack Craft or destroyers are perfectly viable, or even a tanker/tender support vessel if fuel costs are minimal and the real concern is simply logistical.)
Demarquis wrote: ↑Fri May 27, 2022 12:50 am
Missiles on the fighter work out exactly the same way: if the missile is equipped with a smaller version of the same drive design as the fighter is, then it's just a small unmanned fighter, with the same overall performance parameters per kilogram. Why bother with the fighter, why not just launch the missiles from the larger ship? Why doesn't your fleet consist of 100 autonomous missiles (in which case they become drones)?
Production efficiency. To wit, it is far cheaper per-unit to build a small, short ranged missile than it is to build a big, long-ranged missile that's functionally (and financially) equivalent to a manned craft. If you can reuse 75% of your system indefinitely, you can then afford to build far more actual expendable munitions, allowing you to saturate enemy defenses on the tactical level (as your "booster" stages are re-useable) and simply out-produce the enemy on the strategic level. An all-VLS, all-missile strategy will of course always generate bigger salvo weights ("alpha strikes") but those do face a point of diminishing returns (i.e. after you've saturated enemy point-defense and achieved target over-kill margins on hostile hulls.)
Demarquis wrote: ↑Fri May 27, 2022 12:50 am
Now, your concept of a space torpedo bomber is a much better one, and you are not the first to think of it:
http://www.rocketpunk-manifesto.com/200 ... s-not.html (do read the comments section on that website, it's well worth it). However, they aren't ideal for a missile platform, more efficient is using them to fire kinetic slugs (perhaps with some minimal delta-v for minor trajectory correction). Lasers are plausible as well, but if you are firing a missile, just fire the missile from one large launching platform, and leave the "fighter-bomber" at home (or, conversely, the carrier). Rocketpunk calls this design a "Lancer", and of course Lancers (Bombers) can engage each other, at which point they become "Interceptor-Bombers", but not fighters as most people envision them (mostly from movies). From that website:
"Now things start to look interesting, because it has probably already occurred to you that lancer ships can engage each other. In fact, if lancers are technically and tactically viable at all, the best way to protect your big ships from them might be to send your own lancers out to engage them. A battle between lancers even looks quite a bit like a dogfight, though on a vastly larger physical scale. We can imagine small, handy ships, hurtling along complex curved trajectories, trying to line up for clean shots at their enemies while avoiding getting lined up on - especially getting boxed in, where evading one enemy sends you right into the path of another."
I should've known Winchell Chung had already covered this.

This is exactly what I was alluding to with the joke about "torpedo boat destroyers" in my last post, as this is precisely how the naval destroyer of 1930s-1950s came to be. Back when "torpedo" was the term for a naval mine, some madmen would mount them on a pole ("spar torpedoes") and try to do mischief by closing in to ram with small, fast boats. The threat was roughly akin to fireships in the age of sail - considerable, but only in limited circumstances and with luck. Then in 1866 Robert Whitehead invented a
self-propelled torpedo and suddenly these torpedo boats became a
problem. Thus was born a gunship meant precisely to defeat them, the "torpedo boat destroyer," and it didn't take long before people realized that a small, fast, well-armed vessel was quite suited to delivering torpedoes
itself.
Demarquis wrote: ↑Fri May 27, 2022 12:50 am
I'm going to quote myself from another forum, where I described what I thought such a battle would look like: "I imagine that the most likely "maneuver" will be a high-speed pass pat each other. One or both of the ships could end up destroyed in that first pass. If not, then what happens next depends upon how much delta-g the two ships have. If they have the capacity to pull it off, the two ships could turn around for another pass. This would be a very large scale maneuver- curved trajectories hundreds if not thousands of kilometers in diameter. Actually, if they have enough fuel, I imagine them beginning to circle each other at that distance, traversing the circle in a matter of hours or days, all the while firing at each other from across the "circle" (the munitions do not go in a straight line, they also curve around the center of the circle- except for the lasers, of course). Add in a few dozen more ships on each side, and that's what a deep space battle looks like: a slowly spinning swarm of death."
It sounds very much like a high-velocity closing engagement, and while the likelihood of those occurring owe heavily to the tactical/strategic situation for capital ships, when you're talking dedicated fast attack craft with high thrust/weight ratios it's a lot more likely to develop in their own duels. It makes the "Lancer" term even more appropriate.
Arioch wrote: ↑Fri May 27, 2022 10:02 pm
Ships do have thruster nozzles pointing in every direction -- these are maneuvering thrusters. They really don't help a ship dodge, because their thrust is not strong enough to displace the ship even one ship-length in a second, which means most incoming shots will still hit. To effectively dodge, you need to rotate the ship and then accelerate with the main drives. This is something small craft do much better than large craft; because the moment of inertia increases exponentially with ship length, a smaller vessel can turn more quickly than a large one, even if they have the same relative acceleration.
Such a design (as opposed to the oft-seen concept of a space fighter as a unisymmetrical craft with primary thruster nozzles for every axis) also has the advantage of being a bit more mass-efficient, as you're only lugging one thruster nozzle instead of multiple. The devoted "thruster ball" will still be superior at dodging, but inferior at having the dV to make the intercept to begin with, and the ranges at which energy combat are conducted at mean the maneuvering capability of a "traditional" fighter is more than sufficient. (The thruster-ball would definitely have its uses in closer combat and/or dedicated point defense screens, of course!) Incidentally, the traditional layout also allows for aerodynamic streamlining and thus multi-use capability, which is always good given that you have the ships you brought with you and nothing more, to quote a certain strategist.
Arioch wrote: ↑Fri May 27, 2022 10:02 pm
Beam weapons can be "dodged" by evasive maneuvers, with is constantly throttling up and down and rotating to throw off your predicted position in the time it takes the beam to arrive at lightspeed. At 1 light second distance, a 30G change in acceleration can displace more than a ship-length from its predicted location in the 1 second it takes the shot to arrive.
There is also the resolution limitations of targeting sensors to contend with - once your target is a spec that is smaller than the smallest "pixel" you can resolve, you have problems. Of course, people zipping around with improved antimatter drives probably have very nice sensors, but that also goes for their multi-spectral jammers and ECM. But as you say the lightspeed limit really is the defining factor here - not only does it take time for your DEW to reach the target, but it takes time for the light reflected off the target to reach
you! The information flowing into your sensors or even your Mark 1 eyeball is already obsolete. How
much lag is required to generate a miss depends on the maneuvering thrust the target has available and, of course, their overall cross-section, two things that small ships happily tend to have an advantage in.
