User:Jlmr

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KSP is just what I have been looking for! A creative space simulator! Now if the team at Squad would just add little things like, ships, air balloons, zeplins, bombs, guns, missiles, subs, lasers, ground combat, animals, city/nation building, multiplayer, space colonies, space docks, space construction yards, asteroid mining, resources/economy... Hey, I can hope right? =)

Kerbals at War = OMG!!! *drools*

My stuff

Units of measure

  • While units of mass and thrust are not specifically labeled in-game, a bit of logic can quickly determine that thrust is measured in kilonewtons (kN) and mass in metric tons (t). For example, if measured in kilograms(kg), a "9 kg" Rockomax X200-16 Fuel Tank on Kerbin, having a surface gravity of 9.81 m/s2, would be roughly the size of a 48 oz coffee tin and only hold about 1.5 L of fuel. If measured in metric tons, a 9 t Rockomax X200-16 Fuel Tank under the same gravity would be about 0.67 m tall and 2 m in diameter, easily capable of holding the advertised 1600 L of fuel. Only a rocket engine with a thrust around 100 kN could have any chance to lift a 9 t fuel tank.
  • Thrust to weight ratio at sea level on Kerbin is calculated by the following equation, which applies only to liquid or solid fuel rocket engines, jet engines use a complicated formula on a vehicle to vehicle basis.
TW=T kN(m t)(g0)

where:

T is the thrust is the thrust obtained from the engine, in kilonewtons.
W is the weight of the engine at sea level on Kerbin's surface.
m is the mass of the engine in metric tons (t).
g0 is the acceleration at sea level on Kerbin's surface, in m/s² (≈9.807 m/s²).
  • Specific impulse at sea level on Kerbin is is calculated by the following equation.

Justification for t and kN (or 1000's kg and 1000's of N)

  • An official NIST/SI publication: http://physics.nist.gov/Pubs/SP330/sp330.pdf states that kilonewton (kN) is a valid SI unit to represent 1000 N and ton (t), while historically a non-SI unit, has been accepted for use in the SI system by CIPM as a valid unit to represent 1000 kg for just over a century.
  • We already know that the game uses SI units. These are specifically labeled: meters for units of distance, meters/sec for acceleration, liters for fuel volume, and liters/sec for fuel consumption.
  • We know that the Mk1-2 Command Pod weighs 4 "units" from the in-game description. The command pod is roughly 2 m in height and 2 m in diameter. Calculating it's total volume gives us about 2.09 m3. Let's assume the capsule has 0.05 m (2 in) thick walls and subtract the interior void to get only the volume of the capsule walls. This gives us a volume of 1.80 m3.
    • Knowing the volume of the walls, we can calculate the density of the material making up the capsule, taking the 4 in-game units to mean kg, this comes out to be about 13.79 kg/m3. Unfortunately, is about 72.29 times less dense than water at room temperature and closer in density to most gasses! Perhaps Kerbals have discovered a super strong gas-like substance to make spaceships from? =)
    • However, if we take the 4 in-game units to mean metric tons, we get a density of around 13793.10 kg/m3, well within the range of the density of real building materials.
  • The wikipage on Kerbin states it has a surface gravity of 9.81 m/s2, roughly that of Earth.
    • Given this we can calculate the following. If measured in kilograms(kg), a "9 kg" Rockomax X200-16 Fuel Tank on Kerbin, having a surface gravity of 9.81 m/s2, would be roughly the size of a 48 oz coffee tin and only hold about 1.5 L of fuel. Unfortunately for our intrepid Kerbals, 1.5 L of fuel would not provide enough energy to lift a 9 kg payload through 75,000 m of atmosphere, much less a few hundred meters.
    • If measured in metric tons, a "9 t" (9,000 kg) Rockomax X200-16 Fuel Tank under the same gravity, being about 0.67 m tall and 2 m in diameter, gives a volume of 2104.87 L, more than enough to hold the advertised 1600 L of fuel. Only a rocket engine with a thrust around 100 kN (100,000 N), could have any chance of lifting the 9 t (9,000 kg) fuel tank.
    • Similarly, a substance weighing only 8 kg with a volume of 1,600 L has a density of 5 kg/m3, only about three times greater than the density of gaseous oxygen, and would not make an efficient fuel. Whereas, a fuel weighing 8 t with a volume of 1,600 L has a density of 5000 kg/m3, closer to a realistic rocket fuel.

My "Sandbox"

  • Currently testing column widths and categories to standardize and future proof part tables.

Template:Stats Table Command Pods

Image Part Size Cost ($) Mass (t) Drag Max Temp (K) Tolerance Max SAS τ Crew
Mk1 Cockpit Small 1800 1.25 0.1 3400 45 5 1
Mk2 Cockpit Small 1600 1 0.08 3400 40 5 1
Mk3 Cockpit Mk3 1600 1 0.2 3400 50 5 3
Command Pod Mk1 Small 600 0.8 0.2 3400 14 5 1
Mk1-2 Command Pod Large 1800 4 0.2 3400 45 5 3

Template:Stats Table Liquid Fuel Engines

Fuel (L/s) Isp (s) TVC
Image Part Size Cost ($) Mass (t) Drag Max Temp (K) Tolerance Thrust (kN) T/W ratio atm vac atm vac Gimbal (°)
Rockomax Mark 55 Radial Mount Liquid Engine Radial Mounted 850 1.5 0.2 3600 7 120 8.2 8.7 7.4 280 330 1.0
LV-T30 Liquid Fuel Engine Small 850 1.25 0.2 3600 7 215 17.5 13.7 11.8 320 370 -
LV-T45 Liquid Fuel Engine Small 950 1.5 0.2 3600 7 200 13.6 12.7 11.0 320 370 1.0
LV-909 Liquid Fuel Engine Small 750 0.5 0.2 3600 7 50 10.2 3.4 2.6 300 390 0.5
Toroidal Aerospike Rocket Small 850 1 0.2 3600 20 250 25.5 13.1 13.1 390 390 -
Rockomax "Poodle" Liquid Engine Large 600 2.5 0.2 3600 7 220 9.0 16.6 11.5 270 390 2.5
Rockomax "Mainsail" Liquid Engine Large 850 6 0.2 3600 7 1500 25.5 109.3 92.7 280 330 1.0
LV-N Atomic Rocket Engine Small 1700 2.25 0.2 4000 12 60 2.7 5.5 1.5 220 800 1.0

Template:Stats Table Solid Fuel Boosters

Solid Fuel Density is 1273-1910 kg/m3 - (Sepratron 1 fuel density is 31831 kg/m3) Mass (t) T/W ratio
Image Part Size Cost ($) Full Empty Drag Max Temp (K) Tolerance Thrust (kN) Full Empty Burn (s) Isp (s)
RT-10 Solid Fuel Booster Small 450 3.5 0.5 0.3 3600 7 250 7.3 51.0 25 212
Rockomax BACC Solid Fuel Booster Small 800 6.75 0.75 0.3 3900 7 550 7.6 68.0 30 280
Sepratron I Radial Mounted 100 0.15 0.05 0.3 3600 7 20 13.6 40.8 5 102

Template:Stats Table Jet Engines

Isp (s) TVC Intake
Image Part Size Cost ($) Mass (t) Drag Max Temp (K) Tolerance Thrust (kN) T/W ratio Fuel (L/s) atm Gimbal (°) Airflow Size Power
Basic Jet Engine Small 950 1 0.2 3600 7 100 10.2 0.3 1456 stall - 7282 max 2.5 200 1.1 125
TurboJet Engine Small 950 1.2 0.2 3600 7 150 12.7 0.4 546 stall - 8192 max 2.5 60 1.0 200