Gamemaster Spacecraft and Space Warfare (IF)

Space warfare after the Icarus Fall is shaped by the realities of propulsion, detection, and the cost of reaction mass. Space flight is less about “speed” in the traditional sense and more about acceleration (how fast a ship can change course or velocity) and delta-V (the total change in velocity a ship can sustain before exhausting its propellant). While constant-acceleration craft simplify maneuvering compared to present-day delta-V–limited ships, battle is still defined by geometry and fuel discipline. High-G burns are decisive but costly; every ton of reaction mass spent on maneuver is unavailable for later pursuit, retreat, or course correction.

Combat Ranges

Space combat and interception are measured in light-time bands — how long it takes information to go out and effects to come back. The ranges are separated by orders of magnitude rather than linear steps because it is vastly harder to cross the final increment into a closer band than it is to move within one. Approaching a target in space requires matching its velocity and controlling closing speed; closing from one band to the next demands a disproportionate amount of delta-V and exposes you longer to defensive fire. Fleets typically approach on oblique vectors to control range, and most combat involves holding or opening distance rather than charging straight in.

Boarding range runs from zero to 1 millilight-second (about 300 km). This is grapples, breaching, and point-blank tools. Precision railgun hits are only practical at the sub-millisecond end, where time-of-flight is short enough for live tracking. Anything further is too far for true boarding but close enough to risk return fire.

Close range covers 1 to 10 millilight-seconds (about 3,000–30,000 km). Lasers and ion lances are most effective here. Mass drivers can be used for precision hits at the short end or for creating debris fields and flak curtains at the long end. Interceptors working this close burn hard to hold the range — too much delta-V is spent just on staying in knife-fight distance.

Medium range spans 10 millilight-seconds to 1 light-second (about 30,000–300,000 km — roughly Earth–Moon distance). At this range, direct-fire weapons that are not relativistic can hit large, predictable targets such as capital ships or stations using predictive targeting. Against nimble fighters, hits are only possible if their maneuver options are heavily constrained. This is the most common range for ship-to-ship duels.

Long range runs from 1 to 10 light-seconds (0.003–0.02 AU). Here, missiles, drones, and attack craft dominate, relying on onboard guidance rather than continuous control. Firing solutions are more about steering the target into the intercept corridor than aiming at a point in space.

Extreme range is 10 to 100 light-seconds (0.02–0.2 AU, or up to 30 million km). This is the realm of strategic strikes — realkanon shots, long-burn missiles, and slow-approach attack craft. Engagements here depend on pre-plotted firing windows and the ability of the projectile or craft to retain accuracy and energy over long flight times. This range pushes the limits of both missile delta-V and neutral-beam cohesion.

Surprise and Engaging the Enemy

Ships at high relative speeds cannot effectively engage each other, the close-range time window is too short. This requires matching velocities, approaching at slow relative speed. With post-Fall radar clutter, it is impossible to detect approaching ship at range, both sides have to rely on scout craft, which must return to base to report. This opens up various surprise scenarios.

Deep Space Interdiction Almost all space encounters happen near a destination. Engaging ships in deep space transit is almost impossible. Travelling at huge velocities, any encounter far away from a destination only lasts minutes, and with no warning it is impossible to engage an enemy under these circumstances. If you have intelligence on how the target is about to travel it is possible to intercept at slow relative velocities, making this a standard engagement, from most distant to closest.
Standoff Artillery The attacker foregoes stealth and pelts the target with artillery at extreme range. The defender can calculate the attackers position and send its own fighters to interdict. This turns the tables, forcing the defender to counter-attack, but only works against stationary targets - even ion engines allows you to duck this type of attack. The attacker benefits from scout craft to act as forward observers and a rely chain to forward scout reports back to the artillery platform.
Distant Launch This is a low risk ow reward strategy. Launch fighters at long range with the carrier travelling at high speed relative to the target. Running cold and only powering up at attack range, this can bypass outer defenses, but the combat window is short, only allowing for a single attack run before velocity carries the fighters out of range. The carrier diverts its path around the target to pick up its fighters afterward. This pickup position is the most dangerous point, the defender can calculate approximately where it is to be and launch its own fighters to intercept.
Close Launch This is a high risk, high reward strategy. The carrier runs cold on a trajectory that ends up near the target at low relative velocity and coasts in without accelerating, only releasing fighters very close to the target. If this achieves surprise it gives the fighters a much longer attack window, potentially inflicting a lot of damage. If detected on approach the carrier is a sitting duck and will have to launch its fighters as a defense when the target sends its own fighters.

Battle Environments

Deep Space – The preferred arena for large-scale battles. No gravity wells to distort orbits; geometry is straightforward and predictable. Engagements occur in three dimensions but are easier to coordinate.
Combat in a Gravity Well – Every thrust alters your orbit, creating complex and counterintuitive motion. Surprise and timing are critical, but engagements are harder to sustain. Fleets often avoid major battles close to a planet unless a target in low orbit demands immediate destruction. The exception are very large and shallow gravity wells like that of Jupiter or the Sun – as long as you are not too close to the primary, this is effectively deep space.
Combat on a Space Habitat: Habitats presents two terrains unlike either gravity or microgravity. The first is the central zero-gravity region. From here, you can jump to nearly any point on the inner surface — if your aim and braking are good. Get it wrong, and you’ll either drift helplessly or slam into the wrong spot. The second is the outer hull. Gravity here seems to pull away from the hull, but if you let go, you’re flung along a tangent — not straight out. As you approach the hull, it slides sideways beneath you, making it hard to grab hold of. Staying close requires constant acceleration toward the surface. Spin gravity makes bullets deflect 'upwards' towards the center of spin and are useless beyond 10 meters or so.

Tactical Zones

Space battles often move through three overlapping ranges:

Long Range – Artillery exchanges and standoff weapon use. Detection and interception dominate; neutral-particle projectors are most effective here.
Mid Range – Attack craft engage capital ships; point-defense fire and interceptors try to thin the attackers.
Close Range – High-G maneuvering and rapid vector changes. Interceptors and boarding craft fight in short, violent passes where fire windows are seconds long.
Boarding – Large, predictable targets like habitats and ion-drive ships can be swarmed, but doing so consumes enormous amounts of reaction mass. Boarding actions are dangerous and rarely attempted without total surprise or overwhelming suppression. Still, boarding is an alternative to destroying a target that just won't give up.

Combat Roles

Artillery – Long-range fire support, often delivered by neutral-particle projectors. Effective against static or slow targets; less useful in fast-moving engagements. Vulnerable if caught without escorts.
Carriers – Project force through wings of small craft. Typically form the backbone of offensive fleets, with heavy point-defense arrays to protect against counterattack.
Interceptors – Short-range defense and close-in attack. Operate from carriers or bases; burn reaction mass rapidly in high-G dogfights.
Attack Craft – Medium acceleration, long endurance. Specialize in independent strikes, coasting cold for stealth before attacking and disengaging.
Boarding Craft – Close to a target and match velocity for capture. Only viable after suppression of defenses.

Weapons Employment

Lasers – Ideal for short to mid-range precision fire; point-defense staple.
Neutral Particle Projectors – Long-range, high-damage artillery; cannot be intercepted.
Charged Particle Weapons – In atmosphere, act as lightning projectors; in space, serve as short-range disruptors for electronics and crew.
Missiles/Drones – Effective at short to medium range; long-range missiles are rare due to navigation difficulties in the post-Fall environment.

Operational Realities

Fuel Discipline – Commanders must balance decisive acceleration with the need to preserve reaction mass for later phases of a battle.
Crew Endurance – Even with gene therapy, sustained high-G maneuvers are limited by human physiology. Combat at 5G is near the practical maximum without artificial support.
Civilian Conversions – Many “warships” are converted mining or cargo craft. In emergencies, habitats can be armed rapidly if enough raw material is available.

Capital Ships

Capital ships are the backbone of any fleet, serving both as mobile command platforms and the primary source of heavy firepower. They are heavily shielded against radiation and debris, with armor more akin to layers of ablative gravel than the rigid plating of ancient sea warships. This design soaks up hits and sheds energy over time, making them tough to kill outright. Hulls are heavily compartmentalized, and crews operate in vac suits during combat, rendering decompression a slow and usually non-fatal threat.

Capital ships often mount multiple independent power plants and thruster arrays to remain combat-capable even after taking severe damage. Sizes vary dramatically:

Small capital ships lack artificial gravity and can only sustain months-long deployments. If in a task force with capital ships, it is possible to exchange crews, allowing these shups to participate in longer missions. These ships often have fallback rocket engines and are capable of short bursts of acceleration, mainly used to dodge.

Largest capital ships are functionally mobile habitats, crowded with permanent crews, production bays, and the ability to build fighters from scratch.

Two main types dominate the role:

Carriers – These deploy interceptors, attack craft, and boarding vessels. In practice, they become the heavy hitters of a fleet, projecting force through their wings of small craft. Carriers themselves carry extensive point-defense arrays and limited heavy weapons for close defense.

Artillery Ships – The siege trains of space warfare. Their primary weapons are long-range neutral particle projectors, which cannot be intercepted and can hammer static or slow-moving targets from beyond the reach of most defenses. Artillery ships have little use in mobile fleet battles and may arrive only after the fighting is over. However, if built for lower acceleration to save on cost and mass, they require escorts to survive the journey to the target. Different fleets adopt different doctrines, with some insisting on artillery capable of keeping pace with the main force and others treating them as slower, protected assets.

Interceptors

Interceptors are short-range, high-acceleration craft designed for defense and fast attack in the immediate battlespace. Even these limit their sustained burn to about 5G — enough to overwhelm most opponents without killing the pilot. Reaction mass is consumed at a prodigious rate, making interceptors dependent on carriers or nearby bases for refueling and maintenance.

Their role is to dominate close-range engagements, where superior thrust allows rapid vector changes, forcing enemies into high-angular-velocity targeting problems. Interceptors are armed for these knife-fight ranges, favoring high-energy lasers and charged particle weapons, where accuracy and rapid target switching matter more than endurance.

Attack Craft

Attack craft are designed for independent strikes at much greater ranges than interceptors. They sacrifice peak acceleration for longer operational endurance, allowing them to launch from standoff carriers, coast cold to the target for stealth, and strike before returning along a circuitous route.

They excel at hit-and-run attacks against shipping, installations, and isolated capital ships. If intercepted, they can fight back but — like WWII torpedo bombers — they are at a disadvantage against dedicated interceptors. Attack craft often mount turreted weapons for defense against high-angular-velocity targets and carry standoff armaments such as short-range missiles or neutral-particle guns for engaging from beyond immediate point-defense range.

Boarding Craft

Boarding craft are built to match velocity with a target, something only possible against a vessel with low or no thrust. This slow, deliberate approach is highly vulnerable to defensive fire, so boarding attempts require complete surprise or prior suppression of the target’s point-defense systems. Charged-particle weapons are often used for this suppression, as they can fry sensors and electronics without destroying the prize.

For the final approach, boarding craft may use a brief, extreme-G burn to close the last few kilometers quickly. While boarding actions are dangerous, they can be highly profitable — the only way to seize an intact ship or habitat that refuses to surrender.