At the dawn of interstellar expansion space warfare did not really exist, reason for that was the fact that space-faring states had complete monopoly on this technology in their respective regions. Despite perceived absence of adversarial during space travel, expeditionary and military vessels were equipped with rudimentary lasers and ballistic weapons.

Most common use cases for those light armaments were to crack asteroids, take down space satellites or disable orbital defense stations of lesser civilizations. Everything changed after the Great War begun. A completely new branch of vessels that are built specifically for the interstellar warfare had to be created.

After decades of unshackled violence in the deep space and wild experiments like the Overlord-class dreadnought, both the Empire and Federation have settled down on a relatively robust doctrine that represents the most sustainable use of currently available technology in the context of attrition war.

This shared doctrine revolves around three pillars: Impact, Maneuver, Armor, Countermeasures

Impact

Burst Shrapnel Weapons (BSW)

Early on in the Great War, there were few experiments that involved overwhelming enemy forces with a swarm of light fighters. This approach led to countless casualties as son as both larger vessels and fighters themselves were equipped with burst weapons. Small hulls with thin armor were simply too vulnerable for shrapnel and there was really no counter to this type of weapons.

Later, all fighters were replaced by larger vessels with capability to bare heavy armor that is resistant to burst munitions. Flak weapons remained as one of the staples of defense though as they continued being the most effective countermeasure against remote-controlled drones and guided munitions.

Some vessels are also equipped with capital-sized burst weapons, but they have shown to be still ineffective against most armored targets. Instead they are commonly used to create a cloud of heavy shrapnel that shreds incoming drones/missiles and has a chance to impact exposed parts of the enemy ship, like weapons and engines.

Magnetically Accelerated Weapons (MAW)

Most common and effective anti-capital weapons are electrically powered Magnetically Accelerated Weapons. The working principle behind them revolves around a solid metal project being accelerated with high powered magnets and shot towards the target.

The only competitor in efficiency to MAWs are guided missiles and torpedoes, but unlike the latter accelerated projectiles can not be shot down by a single barrage of burst weapons. On the other hand use of MAW against moving targets becomes increasingly difficult at longer ranges. Even with aim-assisting predictive algorithms, each successive shot puts some heavy requirements on the interplay between the pilot and the gunner.

One of the biggest advantage of such weapons is their safety. Unlike rockets, or even the burst munitions MAW rounds contain neither propellants or explosive components. It means that even if the storage space with MAW munitions gets compromised, no accidental explosions can possibly occur.

The only drawback behind this technology are high energy requirements. As mentioned above, projectiles for Magnetically Accelerated Weapons are mere chunks of alloyed metal. It means that without propellant, it is the weapon itself that has to provide the necessary force that launches a magnetically accelerated projectile towards the target. And this force requires obscene amounts of energy.

Autonomously Guided Weapons (AGW)

Missiles, torpedoes and mines that posses capability to autonomously follow a target count among the most effective weapons for space warfare. Unlike ordinary projectiles, they posses capability to freely chase the target by adjusting the trajectory up until the impact. And given the huge amount of variants available, there is a missile for any possible combat scenario.

There are few drawbacks though that hold AGWs back from becoming the ultimate weapon class for space warfare:

• Cost – each missile is a complex piece of technology akin to a small space vessel. High production costs restrict captains from using missiles to only few combat scenarios when the impact is guaranteed, and the target is of high enough value that its destruction justifies the costly investment.
• Physical Vulnerability – missiles lack armor which makes them vulnerable for Burst Shrapnel Weapons. There are also a plethora of countermeasures like the heat traps that can lead a missile off the target, and nimble laser arrays that cause a premature detonation before the impact.

Remotely Guided Weapons (RGW)

This umbrella term covers both Remotely Guided Missiles and Unmanned Space Vehicles. The latter represent a concept that is most similar to light fighters from first years of the Great War. Since any attempts to produce Artificial Intelligence are banned across the human-inhabited space, all Remotely Guided Weapons require a human pilot to function.

This need for manpower restricts amount of active drones a space vessel can operate at the same time. Another shortcoming of RGWs is their vulnerability to electronic countermeasures. While RGWs can not be blinded by heat traps or remotely detonated by lasers, they can be turned inactive if the connection to the pilot’s input is interrupted with elector-magnetic noise.

Some creative solutions for these vulnerabilities, like tethered drones, autonomous signal amplification relays, and autonomous suicide protocols that turn a RGW in an AGW when the connection is interrupted, have been explored. None of them though have managed to elevate Remotely Guided Weapons from their existing niche.

Maneuver

In the vastness of space one has always somewhere to run. Speed and unpredictable turns have always been the most effective measures against being impacted by adversarial projectiles. Because of that all space vessels are supplied with arrays of powerful engines that enable them to freely strafe, pitch, yaw, accelerate and decelerate along all axis.

Armor

Reactive Armor

Reactive armor is a concept that comes from the land warfare – most vulnerable spots of a space vessel are covered with plates that explode on impact. Force of this explosion is pushing away the projectile that caused the impact and thereby nullify the force of above mentioned projectile.

Reactive armor would be a very effective countermeasure if not for Burst Shrapnel Weapons that can obliterate multiple (if not all) cells on a ship with a single impact. Because of the high cost and operational difficulties Reactive Armor is rarely used by neither side of a conflict.

Static Armor

Good old plates of hard metal alloys and other impact-resistant materials. Heavy Static Armor is a paramount for survival in any space battle of the modern age. Most hulls of military vessels sport outer armor that is around one meter thick, with thinner parts accepted by engineers only as a compromise.

In combination with speed provided by powerful thrusters, modern military vessels can be perceived as invulnerable until the adversary gets to impact their engines or other vital systems that can not be hidden behind a thick carapace. When a vessel is static, slow or moves closely enough to the adversary, even the heaviest armor can not protect it for long from hostile Magnetically Accelerated Weapons and missiles.

Because of the extensive use of Static Armor, most military vessels are too heavy for in-atmosphere flights, or planetary landings. This operational restriction to outer space and high altitude orbit makes warships highly dependent on orbital structures, civilian supply fleets and troop transports for repairs, resupply and ground deployments.

Countermeasures

Countermeasures are used to actively negate harmful effects from adversarial weapons. There are multiple sub-classes of countermeasures that are designed to counter specific types of weapons:

Electromagnetic Countermeasures (EMC) and signal jammers are used to make Remotely Guided Weapons inoperable by disrupting their connection with the remote pilot.

Signature Traps (ST) and Heat Traps (HT) are physical objects that get launched from the vessel in order to confuse the Autonomously Guided Weapons and overtake the target priority in their logic. Because of the storage space requirements, only a limited number of ST’s and HT’s can be carried by a vessel.

Direct Laser Countermeasures (DLC) are autonomous laser weapons that can burn AGW and RGW as soon as they are spotted by ship’s radar. Because of high energy requirements and limited impact, DLC’s are only used against small unarmored targets. As external mechanisms, DLC’s are also very vulnerable to smaller impacts like pallets from Burst Shrapnel Weapons.

Conclusion

Because of ships from both superpowers use sophisticated radars, and functioning specifics of a Subspace Engine, ambushes happen very rarely. Most civilian ship get an opportunity to jump away long before they can be impacted by the attacker.

When the fight actually takes place, it happens between either two patrol vessels or expeditionary fleets. Majority of such skirmishers follow a similar pattern:

During the first stage, both forces “greet” each other with a barrage of BSWs. Shrapnel from them prevents both fleets from launching AGWs and causes minor damage that by chance may shift the tide of the battle to one side pretty early if vulnerable countermeasures or engines get impacted.

Second stage of the battle begins with both parties maneuvering and trying to break through each other’s armor with MAWs. In the heat of this fight one of the adversaries may try their luck at launching few RGWs. If they are successful with overwhelming their enemy and manage to circumvent their countermeasures – the battle is technically won. Another major opportunity for a victory comes is one of the combatants loses a power generator or an engine due to a well placed shot.

In most cases escape is not an option as the the fleeing ship gets exposed to MAWs, and surrender is extremely rare among the Imperial crews. Because of that, most skirmishes end in a complete elimination of one of the adversaries.