Engines, Drives, and Power

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This chapter covers what makes a ship move and what keeps it running: sublight engines and in-system travel, Slipstream drives and FTL transit, Power Capacity and overload, Heat and its escalation, and ship gravity.

Sublight Engines

Sublight engines handle everything inside normal space: leaving a Slipstream seam arc, crossing a system to a planet, running down a target, matching a station's orbital vector, and the part of a trip where the ship can still be chased.

Two drive technologies dominate civilian and military use.

Fusion Drives

Fusion drives are the working standard of commercial space. They are cheaper than antimatter drives, maintainable at most frontier ports, legal everywhere, and understood by mechanics across known space. A fusion drive is repaired with available parts and fueled without military supply chains.

A fusion engine runs at Cruise 1, 2, or 3 (see Cruise Ratings below); Cruise 3 is the fusion ceiling. A working ship at Cruise 2 makes a Standard approach in two days. A bulk hauler at Cruise 1 takes six.

Antimatter Drives

Antimatter drives are fast, expensive, politically significant, and loud. Antimatter thrust crosses in hours what a fusion ship crosses in days. When an antimatter drive lights, every ship in the system with working sensors sees the heat signature and drive bloom, and reads it as military capability or corporate money.

The fuel costs more, the maintenance costs more, and operating one without the right credentials draws attention. Fuel containment, safety systems, regulatory tracking, security seals, and maintenance records give customs, insurers, military auditors, and competitors something to check. A civilian vessel with an antimatter drive is worth investigating.

An antimatter engine runs at Cruise 4 or 5. A Cruise 4 patrol ship makes a Standard approach in twelve hours; a Cruise 5 interceptor makes it in six. Any ship running an antimatter engine at Cruise 4 or higher is detectable at Extreme by any sensor grade for as long as the drive is lit.

In-System Travel

Every ship carries two speed ratings. Speed is tactical: it sets how many range bands a ship can change per maneuver in ship combat, and Chapter Fifteen defines it there. Cruise is strategic: it sets the time to move between Travel Bands in normal space. The two are independent. A courier can be Speed 5 and Cruise 3; a bulk freighter can be Speed 2 and Cruise 1.

Cruise is a property of the Sublight Engine. Swapping the engine changes Cruise, and engine damage reduces it (see Engine Damage below). Every hull profile in Chapters Sixteen and Seventeen lists both ratings.

The GM does not compute distances. In-system travel is resolved from three values: the ship's Travel Band, its Cruise rating, and the destination system's Approach.

Travel Bands

A ship in normal space is always in exactly one Travel Band, measured from its destination: the port, station, planet, wreck, or rendezvous the crew is heading for. When the destination changes, the GM restates the band.

Travel Bands use five of the six combat Range Band names; there is no Extra Long Travel Band. When two ships in the same Travel Band begin an encounter, switch to the ship combat rules in Chapter Fifteen and open at Long combat range unless the situation dictates otherwise.

Legs and Intervals

Moving from one Travel Band to the next is a leg. A leg costs a number of Intervals: one for the near bands, two for the far bands.

A full run from a Standard seam arc to dock is 6 Intervals. Departure uses the same legs in reverse, plus the drive charge at the seam (see FTL Transit Procedure below). The ship's Cruise rating sets the length of an Interval in hours.

When the crew travels between two bodies inside a system rather than from the seam to a port, the GM states the leg count by the same band logic: a planet to its own moon or orbital station is 1 Interval, one inner world to another is 2, an inner world to a gas giant is 4, and a gas giant to the seam arc is 2, or the Extreme leg cost if Approach is Far.

Cruise Ratings

The reference speed column is setting background; do not use it at the table.

Cruise 4 and 5 require an antimatter Sublight Engine. Antimatter engines are Restricted (Cruise 4) or Military (Cruise 5) availability, tracked, and expensive to fuel. A civilian hull with Cruise 4 or higher is corporate, ex-military, or illegal.

Approach

Approach is a system stat. It states which Travel Band a ship occupies when it emerges from the standard exit arc, and how many Intervals the outermost leg costs. Every system record in the Sector Atlas carries an Approach value. When a system record has none, use Standard.

Approach belongs to the seam arc, not the ship. A Cruise 1 hauler and a Cruise 5 interceptor emerge in the same band; on a Standard approach they dock 5 days 18 hours apart. An offset exit adds Intervals to the Extreme leg (Offset Exits, below).

Approach examples:

Hard Burn

A ship may push its Sublight Engine to cover ground faster.

• Trigger: The pilot declares Hard Burn at the start of a leg.
• Effect: Treat Cruise as one higher for that leg only. A Cruise 5 ship cannot Hard Burn.
• Cost: Extra fuel of half a Nearby jump charge for the leg (Chapter Twelve, Fuel). At the end of the leg, the engineer makes an Average Craft check. On a failure, the Sublight Engine suffers 1 System Damage. Each consecutive leg under Hard Burn increases the difficulty by one step.
• Signature: A ship under Hard Burn is detectable at Extreme by any sensor grade for the length of the leg. Signature Management does not offset this.

Hard Burn is a travel procedure. Overburn, the per-round combat push, is a Helm action in Chapter Fifteen.

Detection on the Approach

Travel Bands line up with the sensor grades in Chapter Seven. A watcher detects an approaching ship when it enters the outermost band the watcher's sensor grade reaches: Basic at Short, Standard at Medium, Extended at Long, Military at Extreme. Two exceptions apply at any range. A ship broadcasting a transponder is known to traffic control from emergence wherever relay or beacon coverage exists. A ship on Hard Burn, or any ship running an antimatter engine at Cruise 4 or higher, is detectable at Extreme by any sensor grade. Pursuit across Travel Bands is resolved by comparing clocks; the procedure is in the GM Guide.

Engine Rating and Availability

A sublight engine has a rating and an Availability, and they are separate facts.

Rating is Speed and Cruise, bought as separate steps (Chapter Thirteen, Step Four). Each Speed step is +1 Speed above the hull's baseline; each Cruise step is +1 Cruise. Speed stops at the Speed cap for the hull's Scale and operator tier (Chapter Thirteen, Tier Caps). Cruise stops at the drive class: a fusion engine cannot pass Cruise 3, and Cruise 4 or 5 needs an antimatter engine fitted as a full replacement.

Availability is who may legally own the drive. The drive class sets it.

A hull fits an engine above its operator tier's standard Availability as its one above-standard system (Chapter Thirteen, Component Availability).

Overburn: An antimatter engine (Restricted or Military) adds 1 more Speed while Overburning, for +2 in all (Chapter Fifteen). It also draws attention, needs restricted parts, and typically triggers inspection when found on a civilian hull.

Component condition, salvage, and integration are in Chapter Ten. Build point costs and caps are in Chapter Thirteen.

Engine Damage

When a ship's sublight engine suffers System Damage, the effects depend on how much it has taken:

• 1 System Damage: Reduce Speed by 1 and Cruise by 1 (minimum 1) while the damage persists. Overburn costs 1 more Heat. Hard Burn is unavailable.
• 2 System Damage: Reduce Speed by 2. Cruise is 1 regardless of rating. Overburn is unavailable until repaired.
• 3 System Damage: The engine is offline. Speed drops to 1 (maneuvering thrusters only). The ship drifts and cannot change Travel Band without assistance.

A disabled sublight engine does not prevent Slipstream transit if the drive is intact, but the ship cannot reach the seam arc without assistance.

Travel Pressure

A Cruise 2 freighter that emerges at a Far system through a Distant offset faces an Extreme leg of 10 Intervals and a total of 14 to dock: four days and sixteen hours of fuel, food, and deadline. A Cruise 4 military cutter emerging on the standard arc of the same system docks in twenty hours, and everyone in the system sees its drive from the moment it lights.

Slipstream Drives and FTL Transit

Slipstream corridors are naturally occurring channels in folded space, anchored between distant black holes and accessible at seam arcs where local gravity weakens the boundary between normal space and Slipspace.

The Slipstream drive generates the field required to cross that boundary and sustain transit within a corridor. It is the most complex and expensive system aboard any interstellar ship.

Corridor Classes and Transit Times

Corridor class governs capacity: which ships the corridor tolerates and how much traffic it carries. It does not set speed. Chapter Seven gives the largest safe Scale for each class.

Transit time is set by the length of the journey and the route's traits. Every published route record in the Sector Atlas carries a travel time; use it when one exists.

A Fast or Slow route trait moves a journey toward the low or high end of its band. A Slipstream drive of Restricted or Military availability completes a journey at the low end of its band, never below the band's minimum; every other drive takes the time the route record or the GM sets.

FTL Transit Procedure

Use this checklist at the table when a ship attempts Slipstream transit.

Step 1: Identify the seam arc. An Established or Maintained seam needs no check. A Frontier, New, or Fading seam needs an Astrogation check at the seam difficulty in Chapter Seven, Seam Checks: Frontier Average, New Severe, Fading Hard and add 1 Bane Die . Chapter Seven also gives the result of a failure.

Step 2: Reach the approach zone. The ship travels the legs from its current Travel Band out to Extreme at its Cruise rating (In-System Travel, above).

Step 3: Charge the Slipstream drive. A functioning drive needs 10 minutes to charge under normal conditions. A drive of Restricted or Military availability charges in 5 minutes. Drive Damage (below) lengthens the charge.

Step 4: Entry. An Established or Maintained seam needs no check. Any other seam needs an Astrogation check at the same difficulty as Step 1. A success enters the corridor. A failure leaves the ship in normal space at the arc; the drive must charge again (Step 3) before another attempt.

Step 5: Transit. Standing directives handle navigation in a clean corridor. Active hazards such as saturation, turbulence, and damage call for transit checks (Chapter Seven, Corridor Transit).

Step 6: Standard exit. The navigator follows the charted stream and lets the drive push the ship back into normal space at the expected exit arc. No check under ordinary conditions. Standard exits are monitored; authorities know when a ship arrives.

Offset Exits

An offset exit takes the ship out of the corridor before or after the standard exit arc: the smuggler's tool, the military scout's technique, and the escape when the expected exit is hostile.

An offset exit is an Astrogation check at Average difficulty, changed by the exit type below. It adds Intervals to the Extreme leg of the approach, and the ship chooses its own emergence direction, so a patrol sitting on the standard arc is not in its path.

This is the only copy of the offset-exit modifiers in this book. Chapter Seven, Chapter Fourteen, and Chapter Nineteen point here.

Offset exit failure table (d6):

A failed offset exit makes the exit messy, visible, or expensive; it does not destroy the ship. An experienced customs officer does not need proof that a ship used an offset exit; the arrival pattern is enough.

Forced Entry

A ship in normal space cannot enter Slipspace where no seam exists without tearing through the boundary.

A forced entry outside a seam arc requires suitable coordinates, a functioning Slipstream drive, an Advanced or Military Directive AI running a navigation package, and a navigator willing to attempt something that almost never works. Possible outcomes include catastrophic drive damage, severe System Damage across multiple systems, crew casualties, emergence in an unintended corridor, uncontrolled phase exposure, or destruction. The GM sets the result.

Forced Entry is not the exploration procedure. Finding a new seam is covered in Chapter Seven, Exploration (Corridor Trace), and the full expedition procedure is in the GM Guide.

Drive Damage

A drive that takes System Damage mid-transit may force an immediate emergency punch-out at the GM's discretion.

Power Systems

Power Capacity is how much the ship's reactor can sustain at once. Power Load is how much the ship is drawing now. When Load exceeds Capacity, the engineer must act.

Power Capacity

Power Capacity is the reactor's maximum sustained output. Routine systems (life support, basic sensors, environmental controls) are always on and are included in the baseline. Only high-output systems are tracked during encounters.

Common high-output draws:

When active Power Load equals Power Capacity, the ship is at maximum sustained demand. When Load exceeds Capacity, the engineer must immediately choose one response.

Overload responses:

An overload of 1 above Capacity may run for 1 round without consequence if the engineer declares a response that round. An overload of 2 or more, or an overload still unresolved at the end of the round, escalates: the ship takes 1 System Damage to Power Distribution and the engineer must choose a response again.

Reactor Overload

The engineer can push the reactor beyond its rated output.

• Action: An Engineering Action (Chapter Fourteen) and an Average Craft check.
• Success: Power Capacity is 2 higher until the end of the round. The ship gains 2 Heat immediately.
• Each round it is held: another check and another 2 Heat.
• The ship gains 1 additional Heat.
• Cascade failure: the Reactor and Power Distribution each take 1 System Damage.

Reactor Overload raises Power Capacity. Boost Power (Chapter Fifteen) diverts the power the ship already has to one system. They are different actions.

Emergency Power

Some ships carry emergency battery reserves that activate when the main reactor is damaged, shut down, or overloaded.

Emergency power runs life support, basic maneuvering (Speed 1 from thrusters), the distress beacon, and minimal communications. It cannot power weapons, screens, high-output sensors, or the Slipstream drive. Most commercial ships carry 4 to 8 hours of emergency reserve.

Heat Management

Heat builds as weapons fire, engines push, screens absorb hits, and the reactor works past its rating. The ship removes Heat at the end of each round. Under sustained pressure Heat builds faster than it leaves, and past the Heat Threshold the consequences stack.

How Heat Builds

Heat Dissipation

At the end of each round, the ship removes Heat equal to its Heat Dissipation. This is passive and automatic under normal conditions. The engineer's Heat actions (Manage Heat, Vent Heat, and Reroute Cooling) are defined in Chapter Fifteen, Engineering, and listed with the Engineering station in Chapter Fourteen. Shutting a system down is free (Overload responses, above).

Commercial hull Heat reference:

The baselines for every Scale and operator tier are in Chapter Thirteen, Step Five.

Improving Thermal Performance

Power Capacity, Heat Threshold, and Heat Dissipation are reactor stats. Each step raises one of them by 1, and each stat is bought separately: +1 Power Capacity, +1 Heat Threshold, or +1 Heat Dissipation per step. Chapter Thirteen gives the build point cost of each step and Chapter Ten rates reactor components in the same steps.

Power Capacity and Heat Threshold stop at the caps for the hull's Scale and operator tier (Chapter Thirteen, Tier Caps). Heat Dissipation starts at a baseline set by Scale and operator tier and rises at most 2 steps above it; the second step needs Advanced Thermal Control.

Availability and rating are separate. A Restricted reactor pulled from a wreck runs as well in a freighter as it did in a corvette; Availability decides whether the crew may legally own it.

Heat Threshold Escalation

At the Heat Threshold and above, consequences escalate in bands. Each band includes every penalty of the bands below it.

At Threshold: Warning

• Signature Bloom: all Signature Management checks add 1 Bane Die .

Threshold +1 to +3: System Strain

• Every weapon attack adds 1 Bane Die.
• Every Pilot check to push engines, Overburn, or perform combat thruster maneuvers adds 1 Bane Die.
• At the end of each round: Average Craft check. On a failure, Heat Dissipation is halved (round down) for that round.

Threshold +4 to +6: Critical Strain

• At the end of each round: Hard Craft check. On a failure, the ship suffers 1 System Damage to the Reactor, Power Distribution, or Defensive Control (GM selects).
• Active screens absorbing hits generate 1 additional Heat per hit.
• Heat Dissipation is halved automatically. A Hard Craft check at the end of the round restores normal Dissipation for that round.

Threshold +7 to +9: System Failures

• At the end of each round: Hard Craft check. On a failure, one non-essential active system shuts down (weapons, screens, ECM, or modules; GM selects). Restarting it is an action and an Average Craft check, and generates 2 Heat.
• At the end of each round the ship takes 2 Hull Damage from thermal stress.
• Power Capacity is 2 lower until the ship cools below this band.

Threshold +10 or more: Emergency Shutdown

• At the start of each round, before any other action: Severe Craft check to hold off emergency shutdown.
• On a failure, or if no check is made: all weapons, screens, modules, and ECM go offline. Engines drop to Speed 1 with no Overburn. Life support switches to emergency reserves.
• On a success: shutdown is held off for this round. Each keeps one named system online, and each kept system generates 2 Heat at the start of the next round.
• Recovery: the ship must cool to Threshold +3 or lower before restarting systems. Each restart is an action and an Average Craft check. Life support restarts without a check.

Chapter Nineteen prints this ladder as a quick-reference table.

Gravity Systems

Every ship above Scale 3, and every Scale 3 starship with a Slipstream Drive, carries artificial gravity as part of Life Support. It costs no build points. Ships hold 0.8g to 1.2g across inhabited sections, which has no mechanical effect.

What gravity does to characters (microgravity, elevated and high gravity, sudden changes, and gravity gear) is in the Player's Guide, Chapter Ten. This section covers the ship system.

Controlling Ship Gravity

Standard artificial gravity affects the whole ship at one setting. An engineer changes it with an engineering action.

When a ship's gravity system fails (power loss, System Damage, or a deliberate cutoff), the affected sections drop to microgravity and everyone there makes the check for losing gravity in the Player's Guide, Chapter Ten.

Zone Gravity Control

Zone Gravity Control is an optional core system (Chapter Thirteen, Step Six): 6 build points, standard at no cost on Military hulls. It lets the engineer set different gravity in sealed compartments: 3g in a boarding corridor while the bridge holds 1g. A crew in Funtari hover suits fights normally at 3g while boarders without gravity equipment take the High gravity penalties.

Funtari Hover Integration

Funtari-built ships above Scale 3 often build localized anti-gravity into their interiors: control stations and secure areas placed across open gaps that hover-equipped crew cross easily. Standard artificial gravity handles crew comfort; the hover architecture controls access.

Gravity on Planetary Approach

Most ships keep artificial gravity on through atmospheric approach, holding the normal range whatever the surface gravity. A ship whose gravity system is disabled or damaged subjects its crew to the local gravity band until the system is restored or the ship departs.

Atmospheric entry and landing are in Chapter Nine.