(Hull Volume) x (Wgt Modifier) x (thickness in cm)3D True Wgt |
5. Note the hull's volume in cubic meters from the Fire, Fusion & Steel Hull Size table. 6. Determine the hull type.20 7. Multiply the hull's displacement tonnage by the |
Hull Type Resistance % of Hull Price Displacing Modifier Fluid Deep Displacement 0.9 90% 0.75 Parallel Displacement 0.7 75% 0.85 Curved Displacement 0.5 50% 1.00 Planing 0.3 30% 1.10=09 Hydrofoil (at speed) 0.1 10% 1.50=09 Submerged submersible 0.9 100% 1.50=09 Surfaced submersible 0.5 80% 1.50=09 Submerged submarine 0.3 100% 2.00=09 Surface submarine 1.0 90% 2.00=09 |
The result is the weight of the fluid displaced by the hull.20 9. Compare the weight of the hull with the weight of the displaced fluid. If the fluid weighs more, the vessel will float, if the vessel weighs more, it will sink. In that case, build a larger hull or choose a lighter hull material. |
Calculate hull resistance-- Use the formula R=3D(=C3WD) x rf where =C3WD is the square root of the hull's displacement multiplied by the percentage of the hull actually in the water and rf is the hull resistance factor found with each hull type in the Hull Types table. The result is R: hull resistance. |
Calculate power needed to reach design speed with fully loaded hull-- Do this with the formula P=3D(RV^2/2)where P is power in kilowatts, R is the hull's resistance calculated in the previous step, and V is the top design speed. If you wish to calculate the power in megawatts divide the result by 1000 or calculate the power needed with the formula P=3DRV^2/2000. |
Weight3D ton per meter in diameter of wheel, screw, jet, or tunnel. Volume3D KL/meter in diameter of wheel or screw. KL/ton3D internal hull volume used for power transmission. Cost3D Credits per meter in diameter of wheel, screw, jet, or tunnel. |
Sail Power-- The power generated by wind on sails is determined in a standard atmosphere by this procedure: 1. Multiply the wind velocity in kilometers per hour by 0.28 to convert the wind velocity to meters per second. 2. Calculate the power available in watts with this formula. P3D {[(1286)S]V} 0.1 Where P3D power in watts Where S3D sail area Where V3D wind velocity in meters per second |
When the total sail area is determined, calculate the potential speed expected at several wind velocities. Do this by calculating the power generated by the wind at various wind speeds, then calculate the potential speed with the formula: V^2=3DP^2/R where P is force in kilowatts and R is hull resistance. This formula is based on kilowatts of power modified by the resistance of vessel's hull. Use the formula R=3D(sqrt(WD)) x rf where WD is the hull's20 displacement multiplied by the percentage of the hull actually in the water and rf is the hull resistance factor found with each hull type in the Hull Types table. |
For each point of rowing ability, the rower is able to increase power output by 40% of the basic wattage value. As an example, an individual with Strength 7 (DM+1) and Constitution 7 (DM+1) has two points of rowing ability. Accordingly, the individual's basic wattage value is increased by 2 x 40% or 80%. This means that: 35 basic wattage x 1.83D 63 watts of total power. |
Oars weigh 10kg each and cost CR10 each.20 Paddles-- Light water craft may be propelled with paddles. Though this is similar to rowing a vessel with oars, less power is transfered because paddles have no leverage. A paddle will transmit 60% of the power generated by a rower using an oar.20 Paddles weigh 2 kg and cost CR10 each. |
2. Detemine the material volume (MV) of the superstructure by the following equation: MV3D (2x(superstructure height) x (superstructure length + superstructure width) + (superstructure length x superstructure width))/100 The minimum superstructure thickness should be 0.25 cm. |
Sonar is the sea equivalence of Radar. It is replaced by EMS sensors at TL-10+. Table 7: Passive Sonar Weight in tons by Tech Level Price=09 Range 5 6 7 8 9 (Cr)=09 3 0.1 0.05 0.03 0.01 0.005 200=09 30 - 1 0.5 0.3 0.01 2,000=09 300 - - 10 5 0.5 20,000=09 3,000 - - - 10 1 200,000=09 Power (MW): Weight/5 Volume (m3): Weight=D72 09 Table 8: Active Sonar Weight in tons by Tech Level Price=09 Range 5 6 7 8 9 (Cr)=09 3 2 1 0.5 0.01 - 5,000=09 30 - 20 10 5 0.5 50,000=09 Power (MW): Weight/5 Volume (m3): Weight=D72 Variable-depth sonar is available beginning at TL7, costs 150% as much as normal sonar, and has a volume equal to Weight=D73.=09 |
Torpedoes-- Torpedoes are designed like submarines, at TLs below 5, they are unguided, at TL5-7 they are typically wire guided, and at TL7 and up they are typically target memory or seeker guided. Torpedo tubes are designed like Space Missles, except with the correct type of control system.20 |
Pressure Hull and Maximum Depth-- A sub's max depth is 15=D7armor value. |
Helicopters, VTOL aircraft and grav vehicles can operate off any vessel with a clear deck area big enough for wingspan or rotor diameter=D71.5, or length=D71.5 for grav vehicles. |
Table 10: Aircraft Catapults TL Type Mass Length Cost Capacity (tons) (m) (MCr) (tons) =09 5 Gunpowder turntable 5 20 0.05 3=09 6 Hydraulic turntable 10 30 0.1 8=09 6 Hydraulic fixed 10 30 0.1 8=09 6 Large hydraulic fixed 15 50 0.3 13=09 7 Steam fixed 40 100 0.8 35=09 |