Latest revision as of 10:02, 24 April 2014

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.

${\displaystyle {\frac {T}{W}}={\frac {T\ \mathrm {kN} }{(m\ \mathrm {t} )(g_{\rm {0}})}}}$

where:

${\displaystyle T}$ is the thrust is the thrust obtained from the engine, in kilonewtons.

${\displaystyle W}$ is the weight of the engine at sea level on Kerbin's surface.

${\displaystyle m}$ is the mass of the engine in metric tons (t).

${\displaystyle g_{\rm {0}}}$ 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