User:Jlmr
From Kerbal Space Program Wiki
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*
Contents
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.
where:
- is the thrust is the thrust obtained from the engine, in kilonewtons.
- is the weight of the engine at sea level on Kerbin's surface.
- is the mass of the engine in metric tons (t).
- 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 ($) | Mass (t) | Drag | Max Temp (K) | Tolerance | Max SAS τ | Crew |
---|---|---|---|---|---|---|---|---|---|
File:MK1COCKPITthumbnail.png | Cockpit Mk1 | Small | 1800 | 1.25 | 0.1 | 3400 | 45 | 5 | 1 |
File:Mk2 cockpit-t.png | Cockpit Mk2 | Small | 1600 | 1 | 0.08 | 3400 | 40 | 5 | 1 |
File:Mk3 cockpit-t.png | Cockpit Mk3 | MK3 | 1600 | 1 | 0.2 | 3400 | 50 | 5 | 3 |
File:Command pod mk1-t.png | Command Pod Mk1 | Small | 600 | 0.8 | 0.2 | 3400 | 14 | 5 | 1 |
File:Mk1-2 command pod-t.png | Command Pod Mk1-2 | Large | 1800 | 4 | 0.2 | 3400 | 45 | 5 | 3 |
============================================
Template:Stats Table Liquid Fuel Engines
Fuel (L/s) | Isp (s) | ||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Image | Part | Size | Cost ($) | Mass (t) | Drag | Max Temp (K) | Tolerance | Thrust (kN) | T/W ratio | atm | vac | atm | vac | TVC | Gimbal (°) |
File:Mk55 radial engine-t.png | 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 | Yes | 1.0 |
File:Lv-t30 small-t.png | LV-T30 Liquid Fuel Engine | Small | 850 | 1.25 | 0.2 | 3600 | 7 | 215 | 17.5 | 13.7 | 11.8 | 320 | 370 | No | - |
File:Lv-t45-t.png | LV-T45 Liquid Fuel Engine | Small | 950 | 1.5 | 0.2 | 3600 | 7 | 200 | 13.6 | 12.7 | 11.0 | 320 | 370 | Yes | 1.0 |
File:Lv-909 small-t.png | LV-909 Liquid Fuel Engine | Small | 750 | 0.5 | 0.2 | 3600 | 7 | 50 | 10.2 | 3.4 | 2.6 | 300 | 390 | Yes | 0.5 |
File:Toroidal aerospike-t.png | Toroidal Aerospike Rocket | Small | 850 | 1 | 0.2 | 3600 | 20 | 250 | 25.5 | 13.1 | 13.1 | 390 | 390 | No | - |
File:Lv-909 large-t.png | Rockomax "Poodle" Liquid Engine | Large | 600 | 2.5 | 0.2 | 3600 | 7 | 220 | 9.0 | 16.6 | 11.5 | 270 | 390 | Yes | 2.5 |
File:Lv-t30 large-t.png | Rockomax "Mainsail" Liquid Engine | Large | 850 | 6 | 0.2 | 3600 | 7 | 1500 | 25.5 | 109.3 | 92.7 | 280 | 330 | Yes | 1.0 |
File:LVN.PNG | LV-N Atomic Rocket Engine | Small | 1700 | 2.25 | 0.2 | 4000 | 12 | 60 | 2.7 | 5.5 | 1.5 | 220 | 800 | Yes | 1.0 |