Hybrid Ship Design System

The Hybrid SDS. This ship design system is a hybrid, using elements from various Traveller ship design systems.  The theories behind this system are that (1) ships are specialized, and cannot have everything, and (2) ships complex enough for most scenarios can be generated with relatively simple rules.

Volumes.  In the tables below, only a few hull volumes are listed (usually from 100 to 900 displacement tons).  Tables which use volume as the primary index are meant to be scalable; multiply the units by 10 to get numbers for hulls displacing  1000 to 9000 dtons, divide by 10 to get numbers for hulls displacing 10 to 90 dtons, and so on.

Modularity.  One side-effect of having scalable indices is that ship design becomes more modular in process: once a ship is designed for certain performance characteristics, adding on to the ship results in a simple calculation of the  incremental requirements for most components.  In other words, the whole ship need not be re-done just because some grapples are added; the ship may simply scale up.

Hull Volume. Select the desired hull from the table below.

For hull volumes 1-9 dtons, divide units in table by 100.
For hull volumes 10-90 dtons, divide units in table by 10.
For hull volumes 1000-9000 dtons, multiply units in table by 10.
For hull volumes 10,000-90,000 dtons, multiply units in table by 100.
For hull volumes 100,000-900,000 dtons, multiply units in table by 1000.

Unstreamlined. Unstreamlined ships include box, slab, dispersed, and closed-structure models.  Unstreamlined ships do not have fuel scoops.  Planetoid hulls are always unstreamlined.
Streamlined. Streamlined ships include cylinder, slab, wedge, needle, and spherical models.  Streamlining costs 5 dtons and MCr5 per 100 dtons of hull.  Streamlined ships have fuel scoops.
Airframe. Airframe ships include tapered cylinder, flat sphere, and wedge models.  Airframing a ship costs 10 dtons and MCr10 per 100 dtons of hull.  Airframe ships have fuel scoops.  Airframe ships may not mount grapples.

For hull length and area, please refer to your favorite design system.

Hull Size Code.  For detection and combat purposes, starship hulls are classified  by displacement as follows:

Armor.  If the ship is armored, then it will be up-armored to the best available.  Consult the table below for its volume and cost requirements.  Planetoids with "armor" are said to be "buffered" planetoids, and are formed by leaving a thicker exterior wall and stronger reinforcements.
 

Drives, Power, and Fuel Systems. Select the desired ship performance (jump, maneuver, and fuel refinery) from the tables below. Maneuvering systems are an effective combination of various thrust agencies.  The result is a balance of fuel and performance efficiency.  The performance numbers range from 1 to 6, with an additional zero-rating category for superdiminished performance.  The drives' context determines the ratings' meaning:

• Jump drives can move a ship from 1 to 6 parsecs per jump.
• Maneuver drives move a ship at 1 to 6 Gs maximum.
• Refineries process 10% to 60% total fuel capacity in one hour.

• Jump-0 drives are for ships which make only in-system jumps (up to 10,000 AU).  These drives take the same amount of jump fuel as a Jump-1 drive, but are only 10% of the volume and cost.  Round all fractions up.
  
• Maneuver-0 drives are mainly for slow in-system cargoliners or for orbit stabilization on starports or weapon platforms.  The drive itself has a maximum acceleration of 0.01 G, but is only 10% of the volume and cost of Maneuver-1.  Round all fractions up.
  
• Power Plant-0 is used on survey satellites, escape pods, and orbital weapons platforms.  They require the same amount of fuel as a Plant-1, but only have 10% of the volume and cost.  Round all fractions up.
  
• Refinery-0 systems refine fuel at 1% total fuel capacity per hour, and has 10% of the volume and cost of a Refinery-1.  Round all fractions up.
  

Heat Containment Note.  For those needing a handwave taking heat generation into account, please note that all excess heat which is not bled off is dumped into a thermal storage coil in the engine room.  The coil subsystem is serviced at port, and the coil itself is usually replaced during the ship's annual maintenance.  Thus ship architects are not burdened with having to plan out nasty pointy radiator fins.

Drive Potential Table. Comparing hull tonnage to drive letter indicates performance of that drive in that sized hull.  Use next larger size hull for intermediate tonnages.  Performance is Gs acceleration for maneuver drives, jump number for jump drives, power plant number for power plants, and refinery rating for refineries.

Drive Volume and Cost.  For each drive letter, this table indicates price in MCr and tonnahe required for jump, maneuver, power, and refineries.

Fuel Requirements.  Jump drives require the usual 10% hull volume of fuel per parsec jumped.  In order to power the maneuver drive, power plants require 1% of the hull volume in fuel per G acceleration.  This allows for about two weeks of operation of the maneuver drive, ship systems, and all turret weapons, or four week's operation of life support and 10% G-rated maneuver.
 

Avionics Package.  When the bridge is installed, the ship is given basic sensors, controls, avionics, and comms.  However, milspec systems may be bought to replace the basic systems. Consult the table below for upgrade specifications. The system sensors are rated at the ship's TL x the ship's size class.

QSDS Sensors Retrofit.  The standard sensors equate to basic sensors in QSDS (A1 P3 J0), while the advanced package equates roughly to the best sensors available for that ship at that TL.

Crew Requirements:

Engineering.  Every ship must have one engineer per 35 dtons of jump, maneuver, power plant, and refinery.

Gunners.  Each working battery must be manned by one gunner.

Stewards. There must be one steward per 8 high and medium passengers.

Medics.  There must be one medic per 20 high and medium passengers and crew.

Cargo Handlers.  There should be one cargo handler per 400 dtons of cargo space.

Command.  There must be one command crew per 6 crew members, including gunners.

Pilots.  There must be one skill-level's worth of pilot per 200 dtons of ship volume.  A ship must have at least one pilot.

Astrogators.  There must be at least one astrogator on ships over 200 dtons.

The Bridge

For craft under 100 dtons, no bridge is necessary.  For craft 100 dtons and greater, the bridge volume is 2% of the hull volume or 20 dtons, whichever is greater.  Power consumption is negligible.  The bridge of large starships is usually broken up into control rooms, logistics, ready rooms and war rooms, and emergency bridges or battle bridges.
 

The Engine Room

The drive system volumes include workspaces for technicians to maintain and operate the ship; in short, the engine room.  About 10% of the drive volumes is the engine room.  In addition, these volumes take into account the maze of conduits used in life support, power generation and distribution, and other critical ship systems.

A ship can allocate no more than 10% of its volume for emplacements and fire control.

There are four basic offensive systems: Laser batteries, Missile batteries, Particle Accelerator (PA) batteries, and Meson batteries.  Each offensive battery has its own benefits and drawbacks, and for each offense there is a defense:
 

Fire Control.  One dton must be allocated per weapon battery for fire control.  Usually, this means several weapons are slaved together into one battery, in order to share one fire control station.  Only like weapons can be slaved together into a battery.

Spinal Mounts.  Some weapons are particularly massive, and form the spine of the ship itself.  This weapon, called the Spinal Mount, can be a particle accelerator or a meson gun.  According to Traveller design rules, no other weapon batteries for that ship may be of the same type as the spinal mount.

Emplacements.  Select the screen and weapon emplacements for the ship.  Lasers, missile launchers, and sand launchers can be installed in any emplacement except for barbettes.  Particle accelerators can be installed in barbettes or bays.  Meson guns can only be installed in bays.
 

Weapons.  Fill your emplacements with weapons from the table below.  Each weapon displaces 1 dton.  (Note that sandcasters are mainly defenses rather than weapons).
 

Screens.  Nuclear dampers and meson screens provide defense against particle accelerators and meson guns.  They fit into 50-dton and 100-dton bays.
 

Hangars. Hangars cost Cr100,000 per dton.  They require a negligible amount of power.

Grapples.  Grapples displace 1% of the grappled ship volume, at a cost of MCr1 per dton of grappling.  Airframe ships may not have grapples.

Cargo.  Cargo space is essentially free.  For cargo loading and unloading, assume a handler can load or unload up to 100 dtons of cargo in approximately one hour. Multiple handlers can divide up the time accordingly, but assume for administrative purposes that loading and unloading always takes at least one hour each.

Cargo Handler Rule of Thumb.  Hire one cargo handler per 400 dtons of cargo space.  At full capacity, the loading and unloading process will then take 8 hours (a hard day's work!).

Offensive and Defensive Rating.  Weapons and defenses are rated according to the following table:
 

Advanced Avionics.  Ships with milspec avionics double the effective range of their weapons.

To Hit.  In order to damage a target, you must overcome its defenses: the offensive total of a battery must be greater than the defenses raised against it.  Screens defend against all appropriate attacks equally.  Sand defends against all laser attacks for one round.

Damage.  The number of hits inflicted is equal to the offensive rating divided by the defensive rating. All weapons except meson guns inflict surface damage.  PAs (and some missiles) inflict radiation damage as well.  Meson guns inflict interior damage only.

Example.  

A 200-dton armored trader with 1 battery of 4 TL12 lasers and 1 battery of 2 sandcasters is being assailed by a 400-dton unarmored corsair.  The trader has a defensive rating of 800 against lasers, and 400 against missiles.  Or, if it chooses to use its laser battery against missiles, its missile defense jumps up to 880.  The corsair has 12 TL 12 lasers, for a total offensive power of 1440.  Thus, it can inflict 1 hit per turn against the trader until the trader runs out of sand canisters.  After that, the trader's laser defense drops to 400 and the corsair will inflict 3 hits per turn on the trader.  

The trader, meanwhile, could fire its lasers against the corsair, for a total strength of 480.  The corsair is not armored, so its defense rating is 400, which means the trader will inflict one hit per turn on the corsair.  However, the odds are not in its favor.