Space Fighter/Analysis

When might Space Fighters be practical?

1. Glass Cannons. Glass Cannons everywhere.
While an inductive argument is not foolproof, a study of military history reveals that defence has usually lagged behind offence. Armor Is Useless in other words. Look at, say, how infantry armour was abandoned for quite a while due to the thickness needed to protect against guns needing too heavy armour to be practical, or how modern carriers need to use active defences to intercept incoming missiles rather than being able to just weather it.

Extending from this, future space combat scenarios may involve spacecraft firing at each other with weapons they cannot survive. If relatively small starfighter weapons can continue to lay the hurt on capital craft, it may be more practical to let relatively expendable strikecraft sortie than risk capital spacecraft whose loss will cost heavily in money and manpower.

While full Battlestars would be wasteful, there can still be a case for carriers. If FTL technology is such that fighters cannot mount FTL drives or the mass demands of doing so will require too large a sacrifice in firepower and delta-v, tenders would be necessary to carry them between battlefields.

For problems with this idea, see (4) below.

2. The Tech Level is low, and orbital combat is a top priority.
Quite simply, space fighters are easier and cheaper to build than large ships. If the setting has a tech level close to what we currently have in Real Life, building a Standard Sci-Fi Fleet of capital ships may simply be impossible, or at least prohibitively difficult and expensive, but small, single-person spacecraft could be realistic enough. In such a setting, fighters would be launched directly from a planet, and combat would take place in orbit or otherwise in nearby space. Space fighters may be the most practical way—or the only practical way—to get any combat capability into space at all in such circumstances. This is the alternative that has come closest to becoming Truth in Television so far.

When might Space Fighters NOT be practical?

1. Reliable point defences exist.
If the universe has PD that can mow down far more aggressively-manoeuvring missiles like cavalry before Gatlings, only blatant Plot Armor can protect sluggish strikecraft from getting torn to pieces even more easily. If there is no Stealth in Space, and if combat takes place over large distances, it could give the defenders plenty of time to detect incoming fighters and try to take them out from afar.

2. Long-range missiles are a viable alternative.
In real life, long-range missiles are an increasingly important part of warfare; the same may be true in space. Instead of fighters, large spacecraft could simply launch robotic missiles at each other from great range. These would have a few advantages over fighters. For starters, a missile doesn't need to make a return trip (or indeed decelerate relative to its target at all), which means it can either carry much less fuel (making it smaller and lighter) or it can carry the same amount of fuel, but use it for manoeuvres that a fighter could not afford to make. The missile could also accelerate more rapidly, both for this reason and because it wouldn't carry a pilot that could lose consciousness from excessive G-forces. All this can combine to make the missile harder for point defences to hit—it could give the enemy less time to react as it approaches, evade point-defence fire more effectively, and present a smaller target. Unlike an Attack Drone (see below), a missile would not necessarily need advanced AI or remote control. It would simply have to track a target, accelerate towards it, and perhaps make some randomized evasive manoeuvres to try and dodge point-defence fire. A missile could also be cheaper than a fighter or an Attack Drone, meaning that more could be deployed -- also making the job harder for point-defence systems. It may still be much easier for the enemy to shoot down missiles in space than it would be on Earth—greater distances mean more warning and more time to react, and no horizon or real limit on the range of point defence weapons means more chances to take the missile out. However, depending on the way Space Fighters would be used in the setting, they may suffer from the same weaknesses to an even greater extent (see above) -- their one advantage would be if they could engage the enemy from a range great enough to make dodging defensive fire possible, while missiles obviously would not have this option.

And of course, there ain't no rule that says fighters can't carry missiles. Indeed, most airborne missiles are carried by fighters (some of which are in turn launched from carriers). Depending on the nature of space technology, this might be the case. Then again, defences may be such that fighter and subcapital missiles don't have the punch to damage capitals; see (4) below. We cannot know.

3. Reliable and inexpensive drones exist.
This depends on a variety of circumstances, including the range at which space combat in the universe takes place, the quality of AI available in the universe, and whether faster-than-light communication is possible, amongst other factors. Unmanned robotic fighters would need either decent AI or some means of remote control, and the possibility of the latter depends on either combat taking place at fairly close range, or the availability of a Subspace Ansible. However, some combination of AI and remote control could be practical—remote control (with a light-speed delay) could instruct the fighter as to its overall goals and priorities, and an on-board AI would handle moment-to-moment decisions that depend on "reflexes" and adapting to quickly changing circumstances. If these problems could be solved, drones would have several advantages over fighters, mainly not needing to carry a pilot. If computing technology is miniaturized enough, the pilot and life support could be replaced with a much lighter computer system—and in space, every gram of mass counts for fuel use and manoeuvrability; also, as with missiles, there would be no need to worry about a pilot blacking out from G-forces. Of course, no pilot also means not putting human lives at risk, and possibly faster reaction times.

Of course, there are some potential problems with this idea—primarily the weight and cost of the pilot-replacing technology. We have no idea if the AI or other control devices needed to run such a space fighter will be lighter than a pilot or—probably more importantly—cheaper than training a pilot and building a piloted craft. Counterintuitive though it might sound, manned vessels might be cheaper than unmanned ones for the purposes of a space fighter; as expensive as it is to train a pilot and add life-support systems to the craft, the cost of the machinery necessary to replace the pilot is entirely unknown. If the necessary AI or ansibles turn out to be prohibitively expensive, it could mean pilots are feasible after all.

4. Highly resilient capital craft.
Modern fighters and bombers are a threat to wet navy capital ships and land fortifications because they can carry weapons that effectively damage them. However, even in space where they do not have to fight against gravity to launch, engineering limits would prevent a relatively small fighter from carrying too big a weapon. As a counterpoint to "Glass Cannons everywhere" though, if future defences such as Deflector Shields scale with size such that even the heaviest strikecraft weapons barely damage capital craft, or not even that, then strikecraft would be effectively useless in the offensive role. While a larger projectile would have more mass, it would also have more space for propulsion, fuel, payload, all the useful jazz. A good existing example of this is the Honor Harrington series, where until recently the aversion of Armor Is Useless meant that subcapital weapons lacked the punch to usefully damage (super)dreadnoughts.

Furthermore, if missiles are sufficiently agile and fast that strikecraft cannot easily catch them either - reference the currently-in-development BRAHMOS II that does over Mach 6, impossible for any current Western air-launched missile, much less the carrying fighter, to catch in a tail-on chase - that would also eliminate their defensive role as a supplement to the point defence screen.