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A Starship Design Tutorial: Basic Design 


If there ever existed a serious strike against Fusion, Fire and Steel; it is the irritatingly obtuse nature of its design sequences. Had GDW done a second book on design sequence examples, or shown a better presence of mind in terms of organizing the material in respect to ship and vehicle designs, we would not have the current problem where players are left slogging through umpteenth chapters trying to tie all of the disparate systems into coherent and workable designs. Ship design is the worst of these, as NO means of explanation is given beyond a cheery "'ere you go" sendoff. And that is a pity, because designing TNE starships is not that difficult! Its harder than building older High Guard ships, where you could do dozens in one night, but it is easier than building MegaTraveller and T4 designs, even though your progress is limited to one or two ships a night.

The problem is one of disorganization on the part of the FF&S authors. I use three basic tricks to make the job easier. First I created a design worksheet format that allows the various subsystems to be calculated and collated easily and logically. Secondly I converted many of the tables in FF&S to units in 100 displacement tons for easier calculations. Thirdly I created simpler formulas for handling various propulsion and fuel requirements. So without much further ado, lets build a starship! All you need are a piece of graph paper, a calculator, a pencil and an eraser (and FF&S too!). You can subdivide one side of the graph paper into two designs, or (as I do it) turn it sideways to do three with some crowding of data occurring.


  1. All of these rules assume the density based design systems from FF&S. That means that a limit of 15 tons per kiloliter is enforced.

  2. Certain systems are deleted from my designs to simplify bookkeeping. These include the mass and price of fuel scoops, cargo hatches and launch ports. I also lump avionics with computers. You may wish to be more exacting. I do add them for the writeup and damage tables.

  3. Record fuel, cargo and missle ordinance mass in parentheses to indicate that these systems are only included as part of the ship's loaded mass. These are not added under the "total" section at the bottom of each design module.

Design Module #1: Establish the parameters of the design

For a basic design I will convert Andy Slack's Hugin scout design someone sent me a few weeks back. After the design name and ship type, record the vessels displacement in both tons and kiloliters. Beneath this record the configuration and tech level. The Hugin is 200 tons/2800 kiloliters displacement, and since the TL is usually not recorded in the earliest CT designs, it will be Tech Level 15. For the configuration I chose a Streamlined Cylinder. Beneath or after the configuration, look up the entry for that displacement on FF&S, pg.11. A 200 ton craft has a material volume of 9, and an unmodified length of 17 meters. On pg.12 look up the modifiers for a streamline cylinder hull; the material volume modifier is 1.1, a hull material price modifier of 0.8, and the length modifier is 2. Multiplying 9x1.1 gives an MVM of 9.9, and 17x2 givens a length of 34 meters. Record these numbers, along with the hull price modifier. Multiply the MVM (18.7) times 100 times for a value of 990; this is the surface area in square meters; record. Divide the the displacement in tons by 100; this is the displacement multiplier, which is a handy way of reducing the math required for some systems. Lastly record the ships acceleration and jump range; the Hugin is originally a 3G and J-3 design, and I have no reason to change those numbers.

Hugin Scout
Displacement: 200 tons/2800 m3
Tech Level:15
Material Volume Multiplier (MVM):9.9
Length: 34 meters
Surface Area: 990 m2
Displacement Multiplier (DM): 2
Acceleration: 3G
Jump: 3

Design Module #2: Volumetric systems

The first allocations are for those systems that take up volume only, without drawing power or requiring crew to serve. These include Maneuver Fuel (MF), Jump Fuel (JF), Jump Drives (JD), and armor plus internal structure.

Manuever Fuel (MF)
To obtain the volume of a single g-turn of fuel, divide the ships displacement in tons by 16. (200/16= 12.5 m3). Now one percent of a ships displacement, if given over to fuel, is equal to 2.24 g-turns at 1G. 25% of displacement gives 56 g-turns. A scout needs a lot of fuel, and I've decided upon 33 hours (66 G-turns) of endurance. 66x12.5= 825 m3 of reaction mass. a cubic meter of fuel masses 0.07 tons. 825x0.07 equals 57.75 metric tons. Record fuel mass in parentheses to indicate that it adds its mass to a loaded ship only.
Jump Fuel (JF)
Jump fuel is always a basic 5% of displacement, plus 5% times the jump number. 5%+(5%x3)= 20% of displacement in KILOLITERS (do not confuse with the maneuver fuel use of tons). 2800m3x0.2= 560 m3. 560/12.5= 44.8 additional g-turns of reaction mass. 560x0.07 equals 39.2 tons mass
Jump Drive (JD)
The jump drive is always the displacement of the jump fuel divided by 5. 560/5= 112 m3. At tech level 15 a jump drive masses two tons a kiloliter (112x2) or 224 tons. A kiloliter of drive equals 0.3 Mcr (112x0.3) or 33.6 Mcr
Armor (MV)
Choosing armor is one of the most important steps. But the Hugin is not a military design, so it doesn't need a good deal of protection. According to FF&S a design needs a minimum armor value of 10 times the design G-number, so the Hugin needs a minimum armor value of 30. Since I want to keep it simple here, and to give the ship good protection against ground threats and light infantry weapons. I chose 3 centimeters of Bonded Superdense (1 cm= an armor value of 28), or 3x9.9= 29.7 m3 of BSD. 1 kiloliter of BSD= 15 tons of mass (29.7x15) or 445.5 tons. 1 kl of BSD costs 0.028 Mcr (29.7x0.028) times the configuration multiplier on pg.12 for a cylinder streamline (0.8) gives a final price of 0.6653 Mcr (rounding up).
Internal Structure (IS)
The formula is the product of the material volume of the vessel (9.9) and the acceleration (3G), divided by the toughness of the armor (28). (9.9x3)/28= 1.061 m3 (x15), 15.915 tons mass, (1.061x0.028) and 0.0238 Mcr.

The top of the design matrix should look as follows:

System Volume (cu. m.) Mass (tons) Price (MCr) Power
MF 825 (57.75) - -
JF 560 (39.2) - -
JD 112 224 33.6 -
MV 29.7 445.4 0.6653 -
IS 1.061 15.915 0.0238 -
Total 1527.761 685.315 34.2891 -

Design Module #3: Volumetric and Power based systems

These include the ships life support and artificial gravity and discretionary electronics.

Life Support (LS)
Being a long term use vessel, extended life support is a must. This is where the displacement multiplier (dm=2) recorded at the top first comes into play. 100 displacement tons of ship requires 11.2 kiloliters of extended life support. 2x11.2= 22.4 kiloliters. The mass and volume of life support are the same: 22.4 tons. 11.2 kiloliters of life support costs 0.7 Mcr and consumes 0.28 Megawatts, or 1.4 Mcr and 0.56 MW.
Artificial Gravity (AG)
Always a must unless you're playing with low tech vessels. A ship requires 14 kiloliters of AG per 100 tons displacement. 2x14= 28 kiloliters. Its mass is two tons per kiloliter, price 0.7 Mcr and power 7 MW per 100 tons displacement= 56 tons, 1.4 Mcr, and 14 MW.
Controls (Ctrl)
Multiply AG volume by 0.1 to obtain controls volume. Multiply control volume by 0.1 to obtain mass. Multiply life support (ls) power by 0.1 to obtain controls price (multiply this number by 0.75 for vessels of tech level 12 and less). Controls consume 0.1 mw for every 100 tons of ship, or 0.2 MW.
Electromagnetic Masking (EMM)
Being a scout ship used for patrol duty, I've decided she needs to have low observability to carry out her duties. EMM simply reverses the AG's volume and mass, so I need 28 kiloliters of EMM weighing 14 tons. Multiply the AG cost x10 to obtain price, and divide the AG's power (in MW) by 5 to obtain the EMM's power requirement. Don't worry about surface area allocation at this time.
At 34 meters length, the largest fixed array PEMS sensor she can carry is a 120,000 km unit. I will back this up with a 180,000 km folding array. And two 480,000 km AEMS units. From the integrated PEMS table, a TL-15 120,000 km PEMS is 1.15 kl, 2.15 tons, 2.15 Mcr, and 0.1 MW. The 180,000 km Folding is 8 kl, 10 tons, 10 Mcr, and 0.2 MW. Each AEMS is 5 kl, 10 tons, 10 Mcr and 25 MW.
Communications (Cmm)
Surface area allocation is a problem with radios on small designs such as this. So I choose two 300,000 km units from pg.49: each is 0.01 kl, 0.02 tons, 0.09 Mcr and requires 10 MW. Two each of 1000 AU Maser (0.03 kl, 0.06 tons, 0.18 Mcr, 0.6 MW each) and 1000 AU Laser (0.015 kl are chosen, 0.03 tons, 0.18 Mcr, 0.3 MW each)

The next module down on the graph paper should look like:

System Volume (cu. m.) Mass (tons) Price (MCr) Power
LS 22.4 22.4 1.4 0.56
AG 28 56 1.4 14
Ctrl 2.8 0.28 0.056 0.2
EMM 56 28 14 2.8
Snsr(all) 19.15 32.15 32.15 50.3
Total 128.46 139.05 49.906 89.66

Module #3: Power intensive systems

These include main engineering, armaments and defensive systems.

Maneuver Drive (MD)
We're using Heplar here. The trick is that you need 5 kiloliters of Heplar for every 100 tons of displacement, times the acceleration number. 5x2x3= 30 kiloliters of drive. Mass is the same as volume. Price is volume x0.01, or 0.3 Mcr. Every kiloliter requires 10 MW, or 300 MW total.
Conta-Grav (CG)
High Efficiency CG lifters are used at TL-15. A ship requires 30 kiloliters, at 20 tons mass, at 3 Mcr, and 10 MW per 100 tons displacement. Mutilplying by our trusty DM gives us 60 kiloliters, 40 tons, 6 Mcr and 20 MW.
The Hugin simply follows the CT requirement of one hardpoint per 100 tons displacement, and I see no reason to change this. Using my old manned lasers at http://www.downport.com/~bard/bard/vera/vera7702.html, I chose a 150 MJ laser turret. These each displace 42 m3, weigh 57.33 tons, cost 0.68 Mcr, and consume 4.2 MW at a rate-of-fire of 10 shots per 30 minute term.

Module #3 should look like:

System Volume (cu. m.) Mass (tons) Price (MCr) Power
MD 30 30 0.3 300
CG 60 40 6 20
LT(x2) 84 114.66 1.36 8.4
Total 174 184.66 7.66 328.4

Module #4: Power plant and fuel

Add and total the power usage from modules 2-3. Usually the remaining unallocated systems, such as fuel processing plants and computers, do not add much to this total. Add + or -5% to this total as you see fit. So far the Hugin requires 418.06 MW. I'll add a few more MWs for the other systems I haven't done yet. I'll settle on 429 MWs as my final power plant. A TL-15 powerplant (PP)generates 6 MW per kiloliter, weighs 2 tons per kiloliter, and costs 0.2 MW. My final powerplant is 71.5 kiloliters, weighs 143 tons, and costs 14.3 Mcr. Powerplant fuel (PPF), for one year, at this tech level is equal to the power output times 0.1, so I need 14.3 kls for h2 (1.001 tons mass)

System Volume (cu. m.) Mass (tons) Price (MCr) Power
PP 71.5 143 14.3 <429>
PPF 14.3 (1.001) - -
Total 85.8 143 14.3 <429>

Module #5: Crew and auxiliary systems

Crew allocation
Using the formulas in FF&S, pg.13, (and bearing in mind the computer multiplier for a TL-15 computer, 0.2) design the ship crew. I need 2 Maneuver, 2 Electronics, 2 Gunnery, 3 Engineering, 1 Small craft (since an air/raft is incorporated in the original design), and 2 Command.
Master Fire Directors (MFD)
Allocate MFDs at this point. Since all of the Hugin's weaponry are manned, these aren't necessary. Usually just one gunnery crew is allocated per MFD.
Computers and Workstations (Cmp)
This ship has two command personnel, so a bridge must be fitted. The 2 Maneuver, 2 Electronics and 2 Command crew each need a 14 kiloliter/0.2 ton/0.002 Mcr bridge workstation. The 3 Engineering crew need normal workstations at half of the displacement of a bridge station. And I need three Tech Level 15 standard computers, each 7 kiloliters/1.4 tons/6 Mcr/0.55 MW.
Staterooms (SSR)
I decide that each command personnel rates a single occupancy small stateroom, and the rest of the crew shares five small staterooms in double occupancy. 7x(28 kls/2tons mass/0.04 Mcr/0.0005 MW)=196 kls/14 tons/0.28 Mcr/0.0035 MW
Fuel Processing Plants (FPPs)
Things get a little tricky in this step. FPPs are allocated according to six hour intervals. At tech level 15, I need 0.2 kiloliters of FPP for every kiloliter of fuel. This covers maneuver and jump fuel only, as the powerplant requires only annual refuels. This totals 1385 klsx0.2= 277 kiloliters for six hours of refining time. This number is too high for my purposes. Since every six hours (every DOUBLING) added of fuel processing time added halves the fuel plants displacement, I decide on an 18 hour fuel processing time. 3x6=18 hours. Then I take the inverse of 3 (0.33) and multiply that by original fuel plant's volume (277 kls, or 92.33 kls. Multiply times 2 to obtain mass. To obtain the price and powerplant divide the fuel volume by 100 (13.85). First multiply this times the price per 100 kls of fuel (0.015 Mcr) then by the inverse integer from before (x0.33) to obtain the price (0.069 Mcr). Secondly multiply 13.85 times the power requirement for 100 kls of fuel (0.5 MW at TL-15) times the inverse integer (0.33) for a total 2.308 MW.
Docking Ring (DRng)
I decide to add a 3 ton/84 kl air/raft. A docking ring will suffice (84 kl)
I need one airlock for every 100 tons displacement. So the Hugin needs a minimum of two airlocks.

I do not need any other basic equipment. This module should look like

System Volume (cu. m.) Mass (tons) Price (MCr) Power
Cmp 126 6 18.018 1.65
SSR(x7) 196 14 0.28 0.0035
FPP 92.33 184.66 0.069 2.308
DRng 84 - - -
AL 6 0.4 0.01 0.002
Total 504.33 205.06 18.377 3.9635

Now we total the "totals" of each module. The vessel has allocated 2420.351 kl/m3. Subtracting it from 2800 kl, I obtain 379.649 kl/m3 of cargo, requiring one large cargo hatch. The craft has an empty mass of 1357.085 tons, and a loaded mass (adding cargo and fuel, but not the air/raft) of 1834.685 tons, well within the density based constraints. She has a total cost of 124.5321 Mcr. Her systems consume 422.0235 MW, leaving a 6.9765 MW surplus.

Module #6: Damage Table Allocations

Divide the ships displacement (2800 kl) by 400= 7 kls. This is the volume allocated to every hit location on the ships damage chart. Add, using the guide on pg. 15 and 16 to lump the sum of each system in one of five categories: electronics, quarters, weaponry, hold and engineering. Electronics includes sensors, computers and workstations, communications, screens, EMM/ECM and controls. Qtrs include the material volume, LS and AG, staterooms, shops and sickbays, and airlocks. Weaponry is offensive systems and "point" defenses like repulsors, nuclear dampers and sandcasters. Hold is fuel, cargo and carried craft. Engineering is power plant, maneuver and jump drives, lifters and fuel processing plants. For the Hugin these numbers are:

System Allocation (kl) # hit locs (=Alloc/7)
Elec 204.06 29.15
Qtrs 283.161 40.45
Weap 84 12
Hold 1862.949 266.135
Engrg 365.83 52.2614
Total 2800 400

Since these numbers must be rounded off to the nearest whole number, with quarters being rounded up, these become:

Elec:29 Qtrs:41 Wpn:12 Hold:266 Eng:52

Now we allocated surface area. Sensors and communicators are lumped under "antenna". The radios have 200 m2 total, the masers and lasers are 1 m2, and AEMS are 10 m2 each, for a total of 224 m2. (224/990)x400 equals ~90.5 hit locations, or a total of 91. EMM radiators are allocated in m2=(displacment in tons)x0.14= 28 m2. (28/990)/400= ~11.31 hit locations, or 11. Other systems include the cargo hatch (20/990)/400 = ~8.08, and the airlocks, (6/990)/400= ~2.424, and finally the launch port, [(4.6^2)/990]/400= ~8.549 hit locations, or 9. Totalling these up gives 121 locations, which is more than enough for j-drive, cg lifters and fuel scoops.

The design is completed.