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Spacecraft Design

Any class A starport has a shipyard which can build any kind of ship, including a starship with Jump drives; any class B starport can build small craft and ships which do not have Jump drives.

The Hull

HullHull CodePrice (MegaCredits)
100 tons12
200 tons28
300 tons312
400 tons416
500 tons532
600 tons648
700 tons764
800 tons880
900 tons990
1,000 tonsA100
1,200 tonsC120
1,400 tonsE140
1,600 tonsG160
1,800 tonsJ180
2,000 tonsL200


A ship may have any of three configurations – standard (a wedge, cone, sphere or cylinder), streamlined (a wing, disc or other lifting body allowing it to enter the atmosphere easily) or distributed (made up of several sections, and incapable of entering an atmosphere or maintaining its shape under gravity).

Streamlining a ship increases the cost of the hull by 10%. This streamlining includes fuel scoops which allow the skimming of unrefined fuel from gas giants or the gathering of water from open lakes or oceans. Streamlining may not be retrofitted; it must be included at the time of construction.

A distributed ship reduces the cost of its hull by 10%. It is completely non-aerodynamic and if it enters an atmosphere or strong gravity it will fall to the surface of the planet. It cannot mount fuel scoops.

A standard-hull ship may still enter atmosphere but is very ungainly and ponderous, capable only of making a controlled glide to the surface. Getting it back into space requires an elaborate launch setup and considerable expense. A standard-hull ship may have scoops for gathering fuel from a gas giant but the process will be much more difficult and less efficient. Larger ships of this type will often carry a specialized sub-craft  to perform the actual atmospheric skimming.


Armour is added in 5% increments of the ship’s tonnage.

Armor TypeTLProtectionCost
Titanium Steel72 per 5%5% of base hull
Crystaliron104 per 5%20% of base hull
Bonded Superdense146 per 5%50% of base hull


Reflec (TL 10): Reflec coating on the hull increases the ship’s armour against lasers by 3. Adding Reflec costs 0.1 Megacredits per ton of hull and can only be added once.

Self-Sealing (TL 9): A self-sealing hull automatically repairs minor breaches such as micrometeoroid impacts, and prevents hull hits from leading to explosive decompression. It costs 0.01 Megacredits per ton of hull.

Stealth (TL 11): A stealth coating absorbs radar and lidar beams, and also disguises heat emissions. This gives a –4 DM on any Sensors rolls to detect or lock onto the ship. Adding Stealth costs 0.1 Megacredits per ton of hull, and can only be added once.

Hull and Structure

Initial damage is applied to the Hull; once the Hull is breached, further damage goes to the Structure. When all Structure Points have been lost, the ship has been smashed to pieces. A ship has one Hull Point and one Structure Point per 50 tons of displacement.

The Engineering Section (top)

A non-starship must have a manoeuvre drive and a power plant.

A starship must have a Jump drive and a power plant; a manoeuvre drive may also be installed, but is not required.

Drive Costs
Drive CodeTonsMCrTonsMCrTonsMCr

Performance by Hull Volume

For manoeuvre drives, the potential is the Thrust number (Tn), which is the number of Gs acceleration available.

For Jump drives, the potential is the Jump number (Jn), or Jump range in parsecs.

The power plant rating (A-Z) must be at least equal to either the manoeuvre drive or Jump drive rating, whichever is higher.


Fuel needed for a Jump depends on the size of the ship and the length of the Jump and is calculated as 0.1 x tonnage x Jump distance. A single Jump of that distance consumes that much fuel.

The amount of fuel required by the power plant depends on the rating of the power plant. The fuel amounts listed will power the ship for two weeks, which is the bare minimum for a Jump-capable starship.

The Main Compartment (top)

The ship’s main compartment contains all non-drive features of the ship, including the bridge, ship’s computer, the staterooms, the low passage berths, the cargo hold and other items.


The size of the bridge varies depending on the size of the ship:

Ship SizeBridge Size
200 tons or less10 tons
300 tons - 1000 tons20 tons
1100 tons - 2000 tons40 tons
More than 2000 tons60 tons

The cost for this bridge is MCr. 0.5 per 100 tons of ship.


The computer is identified by its model number; the computer table indicates details of price, capacity, and tech level available.

Model 175Cr. 30,000
Model 2910Cr. 160,000
Model 31115MCr. 2
Model 41220MCr. 5
Model 51325MCr. 10
Model 61430MCr. 20
Model 71535MCr. 30


Jump Control Specialisation (bis): A computer’s rating can be increased by 5 for the purposes of running Jump Control programs only. This increases the computer’s cost by 50%.

Hardened Systems (fib): A computer and its connections can be hardened against attack by electromagnetic pulse weapons. A hardened system is immune to EMP, but costs 50% more.

Both options can be applied to the same computer by doubling its cost (+100%).


A ship comes with a basic communications, sensor and emissions-control electronics suite, but more advanced systems can be installed. The Dice Modifier applies to jamming and counter-jamming attempts.

Standard8-4Radar, LidarIncldued in bridgeIncluded in bridge
Basic Civilian9-2Radar, Lidar1Cr. 50,000
Basic Military10+0Radar, Lidar, Jammers2MCr. 1
Advanced11+1Radar, Lidar, Densitometer, Jammers3MCr. 2
Very Advanced12+2Radar, Lidar, Densitometer, Jammers, Neural Activity Sensor5MCr. 4


Each stateroom is sufficient for one person, displaces 4 tons, and costs Cr. 500,000. No stateroom can contain more than two persons, as it would strain the ship’s life support equipment. The tonnage and cost of the staterooms includes the life support systems needed to keep the crew alive.

Low Passage Berths

One low passage berth carries one low passenger, costs Cr. 50,000, and displaces one-half ton.

Emergency low berths are also available; they will not carry passengers, but can be used for survival. Each costs Cr. 100,000 and displaces one ton. Each holds four persons.

Cargo Hold

The design plan must indicate cargo capacity. There is no cost but cargo carried may not exceed cargo capacity. Any space left over after all systems have been installed may be allocated to cargo space.

Fuel Scoops

Fuel scoops allow an unstreamlined ship to gather unrefined fuel from a gas giant. Streamlined ships have fuel scoops built in. Adding scoops costs Cr. 1,000,000 and requires no tonnage.

Fuel Processors

Fuel processors convert unrefined fuel into refined fuel. One ton of fuel processors can convert 20 tons of unrefined hydrogen into refined fuel per day. A ton of fuel processing equipment costs Cr 50,000.


Luxuries cost Cr. 100,000 per ton, and make life on board ship more pleasant. Each ton of luxuries counts as one level of the Steward skill for the purposes of carrying passengers, and therefore allows a ship to carry middle and high passage passengers without carrying a trained steward on board.

Ship’s Locker

Every ship has a ship’s locker. Typical equipment carried aboard will include protective clothing, vacc suits, weapons such as shotguns or pistols, ammunition, compasses and survival aids, and portable shelters. The contents of the locker are defined only when they need to be but always contains vacc suits and other useful items. The ship’s locker is usually protected by a biometric lock keyed to the ship’s officers.

Vehicles and Drones (top)

The tonnage and cost covers minimal hangar space, indicating the vehicle is either carried on the outer hull or in a form-fitting compartment on board. For ease of access and for storage of spare parts and equipment, many ships will allocate more space to some vehicles.

Mining Drones: Mining drones allow a ship to mine asteroids. Each set of mining drones takes up ten tons, and allows the ship to process 1d6 x 10 tons of asteroid per working day. The tonnage allocated includes ore handling machinery, allowing the ship to take on ore and transfer it to the cargo bay.

Repair Drones: Carrying repair drones allows a ship to make battlefield repairs with the AutoRepair software or when managed by a character with Mechanic or Engineer skills. Repair drones have the same statistics as repair robots only without an Intellect program.

Probe Drones: Probe drones are for surveying planetary surfaces. Each ton of probe drones contains five drones. Probe drones can be dropped from orbit in disposable entry shells but must be recovered manually. Probe drones are also capable of surveying orbiting satellites, derelicts and other space debris. They can also be used as communications relays.

Escape Pods: This covers the installation of rescue bubbles and other escape pods for the entire crew.

Life Boat, Ship’s Boat, Shuttle, Pinnace, Cutter: These are all small craft, hangared either in or on the ship’s hull.

Air/Raft, ATV: These are vehicles, also stored in or on the ship.

Armaments (top)

A ship has one hardpoint per 100 tons of ship and each weapon system takes up one hardpoint. A weapon system may include multiple weapons – for example, a triple turret contains three lasers, missile launchers, sandcasters or some combination of three weapons.


One turret may be attached to each hardpoint on the ship. If a turret is installed, then one ton of space must be allocated to fire control systems:

WeaponTLTonsCost (MCr.)
Single Turret710.2
Double Turret810.5
Triple Turret911
Pop-Up Turret102+1
Fixed Mounting-0x 0.5

Single, Double and Triple turrets can hold one, two or three weapons.

Pop-Up is a quality that can be applied to any type of turret – the turret is concealed in a pod or recess on the hull, and is detectable only when deployed. A ship with all its weapons in pop-up turrets looks unarmed to a casual sensor scan.

Fixed Mounting weapons cannot move, are limited to firing in one direction (normally straight ahead), and are found mainly on fighters. A fixed mounting costs half as much as a turret of the same type, so a single fixed mounting costs 0.1 MCr., a double fixed mounting costs 0.25 MCr., and a triple fixed mounting costs 0.5 MCr.

Turret Weapons
WeaponTLOptimum RangeDamageCost (MCr.)
Pulse Laser7Short1d60.5
Beam Laser7Medium2d61
Particle Beam8Long3d6 + crew hit4
Missile Rack6SpecialDepends on missile0.75

Missile racks need ammunition – twelve missiles take up one ton of space.

A sandcaster reduces the damage from a beam weapon by 1d6. Sandcasters require ammunition. Twenty sandcaster barrels take up one ton of space, and cost 10,000 credits.


Bay weapons are much larger than turrets, and take up 50 tons of space and one hard point, as well as one ton of space for fire control.

WeaponTLOptimum RangeDamageCost (MCr.)
Missile Bank6SpecialLaunches 12 missiles12
Particle Beam8Long6d6 + crew hit20
Fusion Gun12Medium5d68
Meson Gun11Long5d6 + crew hit50

Missile banks fire flights of twelve missiles at a time.

Meson weapons are unaffected by armour, as the blast only becomes harmful after it has already passed through the hull. Meson guns also inflict an automatic radiation hit on the crew of any target struck.


Screens are defensive systems that protect against specific attacks.

ScreenTLEffectTonsCost (MCr.)
Nuclear Damper12Reduces fusion gun and nuclear missile damage by 2d6, removes automatic crew hit from nuclear missile attacks5050
Meson Screen12Protects against meson weapon damage, reducing damage by 2d65060

A nuclear damper reduces the damage from fusion weapons and nuclear missiles by 2d6 when affected.

Meson screens block attacks from meson weapons by preventing meson decay.

Alternative Drives (top)

Traditionally, the only form of faster-than-light movement in Traveller has been the classic Jump drive, which always takes one week to travel a number of parsecs equal to its Jump rating and consumes a vast amount of fuel. If the Referee wishes to model other science fiction settings with their own forms of stardrive, the classic Jump drive rules may not be entirely appropriate. The alternative drives below use all the same rules as the Jump drive (mass, fuel, power consumption, range) unless otherwise stated.

Some of these drives consume much less fuel or allow much faster travel than the Jump drive, so introducing these drives will vastly impact the carrying capacity of a starship, the profitability of trade, the speed of communication and so forth.

Warp Drive: The ship warps space around it, allowing it to move faster-than-light while staying in our universe. A warp drive does not have a maximum range – instead, the ship’s drive rating indicates the number of parsecs crossed per week of travel. Warp travel consumes fuel at twice the normal rate for the ship’s power plant rather than needing a single massive expenditure in the manner of a Jump drive.

Teleport Drive: The ship instantaneously jumps from one point to another. This works just like the standard Jump drive without the week-long wait in hyperspace. Instead, no time whatsoever elapses during the transition from one place to another. A teleport consumes no extra fuel but jumping is a strain on the ship’s systems and multiple successive jumps can damage the drive.

Hyperspace Drive: The portal drive functions by opening up a gateway into hyperspace, through which the ship can pass. When in hyperspace, the ship uses its conventional engines to travel, then opens up a second gateway back to the normal universe, effectively taking a short cut through a higher dimension. A hyperspace drive is limited by the size of the spacecraft that can pass through the portal – see the Hyperspace Portal table. A hyperspace drive consumes no extra fuel, but takes up twice as much space as a jump drive. While in hyperspace, the spacecraft moves at a rate of one parsec per day per manoeuvre drive rating.

Hyperspace Portal Size

Alternative Power Plants (top)

Traveller posits the development of highly efficient fusion power plants, but other settings may use different sources of power. Unless otherwise noted, these power plants use all the same rules as the standard fusion power plants.

Fission: A fission plant requires radioactive elements as fuel. Fission drives only produce half as much power as a fusion drive of the same type – when calculating required power plant rating, work out the required rating for a fusion drive and then find the rating for a drive that produces twice as much power. For example, a 400 ton ship with manoeuvre and jump ratings of B requires a fusion plant with rating B. Cross-referencing B and 400 tons on the Performance by Hull Volume table gives ‘1’. A fission plant for that ship would have to be rating D or higher, as that is the minimum rating to get performance level ‘2’. Fission drive fuel costs 1,000,000 Cr. per ton. Power plants use the following table to determine how many tons of fuel they consume with a year of operation:

Fission Plant Fuel
Tons of Fuel24681012141618202224
Tons of Fuel262830323436384042444648

Antimatter: Antimatter drives work by annihilating small amounts of hydrogen and anti-hydrogen. No tonnage needs to be allocated to fuel, but the drive must be refuelled once per month, at a cost of 5,000 Cr. per ton of drive.