CFG File Documentation

From Kerbal Space Program Wiki
Jump to: navigation, search

Configuration files are text files used to specify, store and adjust information for various parts of the game in a human-readable manner. They most commonly use the .cfg file extension, but this is not always the case. The most commonly referenced cfg files are part configurations. These are used to change settings for the part such as mass, size and cost, as well as adding, removing or adjusting part modules, for example increasing an engine's thrust or adding resource storage capacity.

Config Format

The config format used in Kerbal Space Program is NOT a Unity class, but specific to KSP.

KSP reads .cfg files into config nodes. Config nodes can contain values (serialized versions of all sorts of data types) or other config nodes. See the C# class documentation in the KSP API Documentation for more details.

Module Manager

The stock config is very simple - nodes and values, which are nothing more than tree nodes and strings. Parsing is handled by modules that use .cfg files. See KSPField in the API.

The mod Module Manager adds powerful filtering and extension capabilities to the Config Node format. If you see an @ signs, []'s, or it looks like programming, the config is using Module Manager. It is well documented in the forum thread and on sarbian's Gitub.

Basic Part Making Guidelines

Every part consists of multiple files, including the configuration file, a model and a collision mesh. Under the 0.25 standards, the model and collision mesh must both have a material assigned when creating them in your modeling software and prior to export for use. I am not a modeler, so I will leave that guidance to someone more qualified.

When creating a new part, each of these files (including additional models and meshes, if needed) should all be contained in a single folder which describes or names the part. Even though Squad themselves are horribly inconsistent when building parts, it is best to have the name of the folder, and the names of each of the meshes match the name of the part inside the cfg file (not the name that you see in the parts building! More on that later).

If you making more than a few parts, you may want to create a folder for each type of part. This is certainly an acceptable practice, and one that Squad uses themselves. For example: /Engines/ to place all of your engine designs inside.

If you are making a mod that does things other than just provide a stock-capable parts pack, you may want a more subfolders, one for parts, one for agencies, another for contracts, etc, etc.

No matter how deep you nest your mods' folders, your mod itself should be contained within the /GameData folder with a name that uniquely identifies your mod. It would be wise to name this folder the same as you are marketing your mod (ie: GameData\Modular Kolonization System\ is advertised as Modular Kolonization System or GameData\MechJeb is advertised as MechJeb) (and yes, I know that I'm using examples which actively violate this principle!)

So, I wrote a mod (let's call it ShadowSplat) that modifies some resources, adds a few agencies, and massively updates the parts pack including new engines, fuel tanks, science containers, and electrics. My folder structure might look like this:


PARTS Configuration Files

As of at least 0.24.2[outdated], the order of the configuration file matters very little. As far as I can tell, you can throw just about anything you want in there in any order. However, for compatability and error-checking reasons, it's best to follow the general structure that exists within stock parts. Many of the stock parts contain commenting-out lines to help you decode where things should go, but, here's a general breakdown, using a mythological part (let's call it "DoesItAll"). DoesItAll will exist in this foldier:


and will consist of the files:


Note: this is a general explanation. Additional information can be found be clicking the provided links:

General Parameters

Actual part Explanation
PART - specifies that this cfg relates to a part
name = DoesItAll set the hidden name of the part. Spaces are not allowed. Underscores and other special characters are either not allowed or not recommended. This name is used behind the scenes for reference to and from other parts and procedural calls, but is also revealed during crash/damage dialog boxes (F3). It is good programming practice to use a name that at least partially defines the part and/or creator. fuelTankSmallFlat (which is already in use) is not a good name to use here, even though it does describe the part effectively, it does not differentiate between an fuelTankSmallFlat - The T-100 fuel tank and the Rockomax X200-8 Fuel Tank, which could also be considered a fuelTankSmallFlat.
module = Part This convention is no longer used. Earlier versions of KSP only permitted individual parts to serve as single modules and this was therefore appropriately placed back then. Newer versions allow parts to have/serve as multiple modules and the conventions for defining those modules have been relocated and redefined as its own subgroup. Can still be found in legacy parts that have not been updated, including the "Tail Fin" by C7 Aerospace Division. 5 parts in total are known to still use this convention.
  • FuelLine has the additional property of maxLength, presumably to restrict the length of fuel lines. This method is used on the Stock Fuel Line
  • StrutConnector has the additional properties of linearStrength, angularStrength and maxLength. This method is used on the stock Strut Connector
  • Winglet has the additional properties of dragCoeff and deflectionLiftCoeff. just like the ModuleControlSurface. This method is used on the stock parts Tail Fin, wingletAV-T1, sweptWing and is expected to be deprecated at the next revision of those parts.
author Simply a place to take credit for your creation / update. This line is not referenced in-game. It is recommended that you utilize the same author credit for all parts that you or your team create under one title. For example, assign all MKS mods to author MKS Team and all OKS mods to author OKS team, even though you are all the same team.

Model Parameters

At this point, you can use the deprecated style of mesh on a line by itself, or open a new sub called MODEL. The preferred method is to use MODEL:

Actual part Explanation
MODEL { opens the MODEL sub
model The name of the mesh. Write its name therein and keep the mesh file in the same directory as the part file.
scale The scale of the model - depending on the units in your 3D modelling program. If you used one unit = one meter, then use a scale of 1. If it's 1 unit = 0.1 meters, then use a scale of 0.1. Using a 0.1 scale factor and then scaling to fit the other parts is easier than fiddling around with scale factors. This factor will only affect the units involved in node placement and will not affect the actual size of the part.
texture Specifies let location of the texture file - e.g. texture = texturefilename , folder/../texturefilename (/folder would be GameData/folder)

If you do not use MODEL, you must use mesh to define the parts collision mesh, like so:

Actual part Explanation
mesh Mesh defines the mesh and texture package used to create the in-game appearance of your part. Acceptable meshes include .mu files.

Asset Parameters

Actual part Explanation
mesh = Mesh defines the mesh and texture package used to create the in-game appearance of your part. Acceptable meshes include .mu files
scale scale defines the size of your part. I am uncertain as to what will happen when you change this value
specPower Specific Power? fuelLine
rimFalloff 3 fuelLine
alphaCutoff Number: 0.0 fuelLine

An optional parameter that is not usually included in most parts, but the option is available for resizing a part for personal use. In order to retain correct node placements, the scale parameter must also be proportionally changed to match the new rescaleFactor. The default value for rescaleFactor is 1.25 but can be changed to any value.

iconCenter 0,3,0 Array of integers? (advSasModuleLarge, fuelLine)

Node Definitions

So, node definitions are a little weird. You don't have to use any, and you *can use a whole bunch. Defines where parts attach to other parts. Tricouplers have four: three bottom and one at the top, while most parts simply have two, and a few parts have only one.

Node stack defines where the part vertically stacks with other parts, and node attach defines where on a part's surface other parts attach - in other words, horizontal attachment.

The attachment values relate to an object's origin, and their values correspond to a model's units and scaling factors. A node_stack_bottom with x, y, and z values of (2.5, 5.0, 3.0) will have an attachment node 2.5 units to the right, 5.0 units up, and 3.0 units forward. The next three values refer to the orientation that a particular node will accept other attachments, on a scale of -1.0 to 1.0. These represent the vector that a part will orient itself on when attaching to the node. For example, a fuel tank with a node_stack_bottom will have angx, angy, and angz values of (0.0, -1.0, 0.0). This represents a vector downward relative to the part model, in the negative y direction. A value of (0.0, -1.0, 1.0) would represent a diagonal vector downward and forward, while a value of (1.0, 1.0, 1.0) would represent a vector to the right, up, and forward.

Generally, most parts will have angx, angy, and angz values of either (0.0, -1.0, 0.0) for a node_stack_bottom and (0.0, 1.0, 0.0) for a node_stack_top.

The last value indicates the visual size of an attachment node. Values may be either 0 (small half-meter node), 1 (normal), or 2 (large). This parameter is optional and will default to 1 if nothing is specified.

Keep in mind, naming conventions (_stack_bottom, _stack_top) for nodes only apply to node_stack; they are only helpful in identifying a node's position.

Known node definitions are listed below:

  • node_stack_top
  • node_stack_bottom
  • node_stack_top2
  • node_stack_bottom2
  • node_stack_connect01
  • node_stack_connect02
  • node_stack_connect03
  • node_attach
  • node_stack_bottom01
  • node_stack_bottom02
  • node_stack_bottom03
  • node_stack_bottom04

Each one follows this example, and specifies where other parts can connect to this part:

Actual Part Explanation
node_attach = 0.00, 0.147, 0.00, 0.0, 1.0, 0.0, 1 specifies the location of the nodes of this part (the green circles).
node_stack_bottom = x, y, z, angx, angy, angz, size
node_stack_top = x, y, z, angx, angy, angz, size
node_attach = x, y, z, angx, angy, angz, size

FX definitions

FX definitions specify visual effects associated with this part, including engine exhausts, explosions, and coloration. Each one is a unique effect, and the only parameters they take is the location/offset that the effect occurs at. The 'active' switch on the end is used to define when this effect will be visible. See the FX Groups listing to know which effect groups are available, and when they are used. It's also possible to assign an effect to more than just one FX Group. If for instance, you want a smoke effect to be visible both when the part activates and also when it deactivates itself, you can do this:

fx_gasBurst_white = x, y, z, angx, angy, angz, activate, deactivate

This is particularly useful if you're defining a lot of effects, like the gas discharges on an RCS module.

 fx_exhaustFlame_yellow = x, y, z, angx, angy, angz, active
 fx_exhaustLight_yellow = x, y, z, angx, angy, angz, active
 fx_smokeTrail_medium = x, y, z, angx, angy, angz, active

Known FX calls are listed below:

  • fx_exhaustFlame_blue_small
  • fx_exhaustFlame_yellow
  • fx_exhaustFlame_yellow_tiny
  • fx_exhaustFlame_blue
  • fx_exhaustFlame_white_tiny
  • fx_exhaustLight_yellow
  • fx_exhaustLight_blue
  • fx_smokeTrail_medium
  • fx_smokeTrail_light
  • fx_gasBurst_white
  • fx_exhaustSparks_flameout
  • fx_exhaustSparks_flameout_2
  • fx_exhaustSparks_yellow


Variable Value Definition
prefabName fx_exhaustFlame_blue The name of the effect you want to use (See list above).
transformName smokePoint The name of the point defined in the Unity editor where the effect will appear from.
size Throttle Range (0.0), Scale (0.0) (Deprecated, doesn't work!) Scales the size of the particle effect set in the Unity editor. This parameter is usually the same number as the size in meters for the part (1.25, 2.5, 3.75, etc.). You need one line with a declaration for every point on the throttle range you are editing (See example below).
energy Throttle Range (0.0), Scale (0.0) Scales the energy of the particle effect set in the Unity editor. Energy is the time it takes for the effect to disappear. For smoke trails, you want a high value, but for water vapor you want a small value. You need one line with a declaration for every point on the throttle range you are editing (See example below).
emission Throttle Range (0.0), Scale (0.0) Lets you edit the emission range and scale of the effect. It handles amount of particles in a set amount of time. You need one line with a declaration for every point on the throttle range you are editing (See example below).
speed Throttle Range (0.0), Scale (0.0) Scales the velocity of the particle effect set in the Unity editor. You need one line with a declaration for every point on the throttle range you are editing (See example below).
localOffset X, Y, Z Used in PREFAB_PARTICLE. Lets you change the offset of the effect in 3D space. To move the particle effect closer to or further from the nozzle, edit the Z axis.
localPosition X, Y, Z Used in MODEL_MULTI_PARTICLE. Lets you change the offset of the effect in 3D space. To move the particle effect closer to or further from the nozzle, edit the Z axis.
localScale X, Y, Z Used in MODEL_MULTI_PARTICLE. This was implemented in KSP 1.4.5 and replaces the size parameter. Lets you change the size of the particle so that the same particle can be custom fit to engines of various sizes. However, values other than [1, 1, 1] only work properly when the engine has (for part makers: only one of the named emitter transform; for casual players: only one nozzle). It works correctly on RCS thrusters that have up to 5 such emitters. This parameter also cannot be used on any of the particles provided by default in the game or by most part mods. New particles must be made such that the same transform that holds the PartTools script also holds the KSP Particle Emitter script.

Example taken from the config file for the S3 KS-25 "Vector" Liquid Fuel Engine:

	prefabName = fx_smokeTrail_light
	transformName = smokePoint
	emission = 0.0 0.0
	emission = 0.05 0.0
	emission = 0.075 0.25
	emission = 1.0 1.25
	speed = 0.0 0.25
	speed = 1.0 1.0
	localOffset = 0, 0, 0

Sound FX definitions

Just like Visual effects, sound effects specify an effect to be used by the part. Sound effects are coded using a two-sided equation, the left side specifies the sound or sound file to be used, whereas the right side specifies when to use that particular sound. Known Sound Effects definitions are:

This is pretty easy to use in a basic way, which will suit our needs just fine.

Under this section, comes:

sound_vent_medium = activate
sound_rocket_hard = active
sound_vent_soft = deactivate

Sounds are added to FX Groups, in much the same way smoke and flame effects are. Of course, sounds do not need to be positioned in space, nor do they have rotations, so all you need is to indicate in which FX Group the sound will be executed. As with effects, you can assign multiple groups to a sound.

Since 0.20 GameData structure there are 2 ways to add a sound to a part:

  • KSP has an internal sound library, which contains a few sound effects. By defining a sound as in the example above, KSP will search for that sound in its internal library.
  • The second way is to add new sound files which is ONLY possible if adding the sound file to the GameData/modName/parts/partName/part/sounds/ folder. Note that all the sounds are therefore "private", only accessed by that part. For now, the legacy folder or a shared mod folder method doesn't work, devs are probably going to fix this problem in the future.

REMEMBER: If you add a custom sound, the file name must start with sound_ (e.g., sound_myNewSoundEffect.wav).

To use a sound from the KSP internal library or the part/sounds folder, you must not include the extension in the sound name (e.g., sound_vent_medium = activate), otherwise the sound will not work.

Supported files are 48000 Hz .wav files and .ogg

These are the paired sound types and part statuses.

Sound Engine Status
sound_jet_low decouple
sound_jet_deep engage
sound_vent_soft running
sound_vent_large power
sound_vent_medium disengage
sound_rocket_hard flameout
sound_rocket_mini activate
sound_decoupler_fire deploy

Editor Parameters

Actual Part Definition
CrewCapacity The number of Kerbals that can be seated in this part. Mk1 Command Pod seats 1. Jebediah is so awesome, he only takes up .7 seats. Chuck Norris takes as many seats as he wants. Use 0 to specify a probe.

This is the technology tree node that must be activated in order to have access to this part. Any single word can go here, but if you use a word that is not in the tech tree definition, you may never be able to access your part. Currently, stock KSP comes with the following Technology_tree nodes:

  • start
  • basicRocketry
  • engineering101
  • generalRocketry
  • stability
  • survivability
  • advRocketry
  • generalConstruction
  • flightControl
  • scienceTech
  • heavyRocketry
  • fuelSystems
  • advConstruction
  • aerodynamicSystems
  • advFlightControl
  • electrics
  • spaceExploration
  • landing
  • heavierRocketry
  • specializedConstruction
  • actuators
  • supersonicFlight
  • specializedControl
  • precisionEngineering
  • advElectrics
  • advExploration
  • advLanding
  • nuclearPropulsion
  • advMetalworks
  • composites
  • advAerodynamics
  • highAltitudeFlight
  • largeControl
  • unmannedTech
  • ionPropulsion
  • largeElectrics
  • electronics
  • fieldScience
  • veryHeavyRocketry
  • metaMaterials
  • heavyAerodynamics
  • hypersonicFlight
  • advUnmanned
  • specializedElectrics
  • advScienceTech
  • advancedMotors

The following Tech Tree nodes are present in stock, but not used unless called for by a mod.

  • nanolathing
  • experimentalMotors

The following Tech makes a part unresearchable and unbuildable but does it not remove from existing ships

  • Unresearcheable
entryCost entryCost represents the amount of Funds required to unlock this particular part. As such, it could be considered an 'investment' cost in the development. First you have to have the brains to make the thing, then someone has to develop it (that's this cost), then you can get it into production (that's cost, coming later). You can set this to any value you like. Bear in mind that this value has no meaning in Sandbox or Science Modes. It is only used in Career Mode.
cost cost represents the cost in Funds to attach a single instance of this part to your craft. It represents the "wet cost", assuming all resources are at their full amount. This is different from mass, which is the dry mass. Cost has no use in Sandbox or Science modes, it is only used in Career mode
category Mods are organized alphabetically according to their sub-directory in parts, and then according to this value. This is why, when you add a mod that is contained in folder "000_NewMod", it's parts appear first and when you add a mod that is contained in "ZZZ_NewMod", it's parts appear last. Currently there are nine useable categories:
  • Command
  • Propulsion (deprecated, but still useable)
  • FuelTank
  • Engine
  • Aero
  • Electrical
  • Structural
  • Utility
  • Wheel
subcategory subcategory is not currently in use as of [0.90]. It is expected that this control will later be linked to [category] to provide a further subdivision of searchable parts in-game, possibly to cut down on clutter when the parts list gets exceptionally high. With certain mods installed, the Propulsion category already spans several pages. [subcategory] can help control this by provided variants such as [liquidEngine], [LOXfueltank], [SRB], etc
title title is the in-game name for your part and features such iconic names as 'Command Pod Mk1'. The title of your part can be as long or short as you want, and there are no known limitations on what can be used in the title. This is how your part will be known in-game, on in-game contextual menus and referred to on message boards and forums (hopefully) so take that into consideration.
manufacturer manufacturer is flavor text (possibly useful in future iterations as a filter for parts) that defines who built or created the part for use (or pulled out of the junk-pile and sold at 10000% mark-up for you to use). Just as with the title of your part, there are no known restrictions on the flavor text, including length. This is KSP, though, so try to be humorous
description description is the flavor text that describes your parts purpose, motivation, direction, life aspirations, goals, favor colors, and (hopefully) what it can (is supposed to) do. As with other flavor text, there are no known limitations on what can go here, including length. In fact, this flavor text is treated special in-game by being given a text box that automatically scrolls based on the length of the description used. If your part does something unusual, it's probably a good idea to (at least partially) document it here, so people know how to use your part in-game. Many are the parts that have failed their popularity exams because of bad descriptions.

Attachment rules

attachRules defines how this part attaches to or allows attachments from other parts. Though documented in some part files, the documentation is minimalist and difficult to understand, so here's a little clean-up and expansion.

  • // attachment rules: stack, srfAttach, allowStack, allowSrfAttach, allowCollision
  • attachRules = 1,1,1,1,1

The rules correspond to the numbers below - 1 is allow, 0 is prevent. The tags are:

stack - Can your part be stacked on others?

SrfAttach - Can your part be placed onto a surface?

allowStack - Will you allow other parts to be stacked on your part?

allowSrfAttach Can other parts be placed on the surface of yours?

allowCollision - A special one: Can your part be placed if part of it is intersecting another part?

Note that you can also force parts attached to this part to attach in a specific symmetry.

  • // symmetry rules: 0=1x, 1=2x, 2=3x, 3=4x and so on...
  • stackSymmetry = 3

Standard Part Parameters

This defines how your part performs in the air and its limits. Note that not all of these parameters need to be defined. If they're left out of the cfg file, KSP will use a default value for them. Standard part parameters indicate how the part interacts with the environment in flight mode. From mounting on the launch platform or the runway through take-off and atmospheric interactions to landing and blowing up, this is where physics enters the game

Actual Part Definition
mass = 1 mass measured in Kerbal tons, describes the 'weight' of your part and is used in calculations involving roll, pitch, yaw, and thrust. The higher the mass, the more energy will be needed to change any of those four parameters. It is also used in making center-of-mass, center-of-lift and center-of-drag calculations, some of which are critical for aerodynamic flight. This is a numerical value, and you can use any positive value. Bear in mind that extremely high positive values for [mass] may make the part unusable in-game or require additional special parts to make usable. This is generally considered poor design. It represents the "dry mass" when all resources are empty. This is different from cost, which is the wet cost.
dragModelType [dragModelType] describes how your part interacts with drag forces. At present, the known [dragModelType]s include:
  • default
maximum_drag (could use clarification) The maximum drag coefficient of the part (usually under between 0.2 and 0.3 and < 1). Generally drag when part's direction of travel is along its y-axis.
minimum_drag (could use clarification) The minimum drag coefficient of the part (usually under between 0.2 and 0.3 and < 1 and lower than maximum_drag). This value is unused if dragModelType is set to default. Generally drag when the part's direction of travel is perpendicular to its y-axis.
angularDrag (could use clarification) how much angular drag is there/resistance to turning? (Also usually under 1.)
crashTolerance crashTolerance describes the maximum velocity (in m/s) at which your part can interact with another part without suffering damage (read: blowing up). The higher you set this value, the faster an impact your part can survive. 12 is fairly high, and is the de facto standard for most pods. 14 is useful for landing legs, and 50 is used on some wheels, which are basically indestructible.

optional [breakingForce] specifies an amount of Force exerted between this part and another part that it is attached to. When exceeded, the two parts will separate (usually catastrophically). Higher values indicate stronger connections.

BreakingTorque optional. Like [breakingForce], [breakingTorque] defines an amount of Force between two parts, but rather than direct force towards or against, [breakingTorque] refers to rotational forces between the two objects. It assigns a value that, again, when exceeded, will cause the two parts to separate, with the expected results
maxTemp Stock KSP uses the [maxTemp] value to determine at what temperature parts will blow up due to overheating. As of Version 1.1, heat sources include Kerbin's sun, re-entry and aerodynamic heating, and engine exhaust. KSP's uses Kelvin as its temperature scale. Once this value is exceeded, your part will spontaneously explode. Managing heat with engines is a critical function of launching higher-powered engines, and design considerations mean that you shouldn't place parts with low [maxTemp] values directly in the path of engine exhaust. ~1800 is a good value for most engine assemblies.
ActivatesEvenIfDisconnected true or false, assumed to specify whether the part will operate when not connected to a vessel (remote control?) Must test. Currently, only know part is the Sepratron I
stagingIcon Sets the icon in the staging system
  • DECOUPLER_HOR (Radial Decoupler Icon)
  • LIQUID_ENGINE (Liquid Engines, or engines that have controllable thrust)
  • SOLID_BOOSTER (Solid Rocket Boosters, or engines without controllable thrust)
  • RCS_MODULE (Small 4-Way RCS Block Icon)
  • FUEL_TANK (Red Fuel Tank Icon)
  • COMMAND_POD (Generic Command Pod Icon)
  • DECOUPLER_VERT (Vertical Decoupler)
  • (?)
stageOffset Can be 0, 1, etc. defines whether this part will create a new stage before itself. This only applies for the automatically generated staging sequence. -1 is used in parachutes...signals that activation of this object does not cause a staging effect?
childStageOffset Can be 0, 1, etc. defines whether this part will create a new stage after itself. This only applies for the automatically generated staging sequence.
explosionPotential unknown purpose. Possibly for future use for random failures. Known values are numerical.
  • 0.1
  • 0 (BSLsnakprobe)
fuelCrossFeed Will the part crossfeed fuel between parts attached to it? allows or restricts fuel moving through this part. Boolean argument: True or False
NoCrossFeedNodeKey = bottom if set to bottom will keep fuel from flowing FROM bottom nodes (avoiding some stack imbalances). Used with parts with multiple bottom nodes, such as the TVR-1180C Mk1 Stack Tri-Coupler. keeps resources from flowing FROM the named nodes (prevents stack imbalances and such) Use with fuelCrossFeed true to to allow resources to flow into these parts, but not back out. Known parameters: bottom
linearStrength The amount of stress the given part can sustain without breaking, in a straight back-and-forth direction. Used for fuel lines and strut connectors.
angularStrength The amount of stress the given part can sustain without breaking, laterally. Used for fuel lines and strut connectors
maxLength The maximum possible length of this stretchy part, expressed in meters. Used for fuel lines and strut connectors, as they have repeating meshes
vesselType unknown. May automatically set the Ship Type variable when including parts with a defined [vesselType]. Known [vesselTypes] include:
  • Ship
  • Probe
  • Lander
  • Rover
  • SpaceObject (refers only to PotatoRoids)
PhysicsSignificance optional. unknown purpose. assumed to default to zero. Appears to be a numerical value. Many parts are 'physicsless' Known parts:
  • radialFlatSolarPanel
  • ladderRadial
  • z-400Battery
  • z-100Battery

Known Values: 1


Each Configuration file is composed of several sections. Some of these sections are standardized across all parts, others are specific to specific part types. To build or modify a successful part, it is necessary to have an understanding of what each section does, and within those sections what each line of configuration actually does, and what the options are for those lines. This Definitions file will attempt to address each of those questions in turn and is current as of [0.25.0]

Notes: It appears that, with a few exceptions, all definitions can occur in any order in the PART file. Free arrangement is valid for MODEL {}, INTERNAL {}, MODULE {},

MODULEs define what specific parts can do. They are generally calls to C-coded or hard-coded functions that define what functionality these parts have in-game.

name names define the module in use and are a general indication of what the module subtype does. Specific variables are associated with each MODULE.[name]. For example, the Clamp-O-Tron Docking Port Sr. has the ModuleDockingNode and its' associates variables are [referenceAttachNode] and [nodeType]. Some MODULEs share variables with other MODULEs, which can make deciphering their purpose difficult.

known MODULEs, their associated variables, and the meanings of those variables will be explained below.

MODULE Name MODULE Function From Modification
ModuleCargoBay Cargo bays Stock
ModuleParachute Parachute Operations Stock
ModuleSAS Control System Stock
KerbalSeat Internal Seating? Stock
ModuleLandingGear One type of Wheel Stock
ModuleSteering For Wheel Operations Stock
FXModuleConstraingPosition Unsure Stock
ModuleLandingLeg For Landing Legs Stock
RetractableLadder For Collapsible Ladders Stock
ModuleReactionWheel Controls Force of Reaction wheels Stock
ModuleScienceContainer Place to store Science Stock
FlagDecal Flag Decorations on Parts Stock
ModuleScienceLab For Science generators Stock
ModuleJettison Fairing removal Stock
ModuleAlternator For producing resources based on thrust Stock
ModuleCommand For Control Stock
ModuleEnviroSensor Unmanned Science Stock
ModuleControlSurface Control Surfaces, aelirons Stock
ModuleAnimateHeat Animation to be played based on heat Stock
Module Engines Engines and Thrust (somewhat deprecated) Stock
FXModuleAnimateThrottle Animation to be played based on throttle level Stock
ModuleEnginesFX Engines and Thrust (use this in place of Module Engines) Stock
ModuleGimbal Engine Directionality Stock
ModuleTestSubject Contract System Stock
LaunchClamp Launch Clamps Stock
ModuleDockingNode Docking Ports Stock
ModuleRCS Reaction Control Systems Stock
ModuleResourceHarvester Harvests resources from the environment Stock
ModuleResourceIntake Intakes that produce resources Stock
ModuleScienceExperiment Controlling Experiments Stock
ModuleGrappleNode For the Klaw Stock
ModuleLight For external lighting Stock
ModuleAnimateGeneric Generic Animation Calls Stock
ModuleDataTransmitter For transmitting antennas Stock
FXModuleLockAtConstraint Uncertain Stock
ModuleAsteroid Unsure Stock
ModuleDeployableSolarPanel For unfoldable solar panels Stock
ModuleWheel For wheels, powered or unpowered Stock
FXModuleLookAtConstraint Unknown Stock
FXModuleConstrainPosition Unknown Stock
ModuleAnchoredDecoupler Decouplers1 Stock
ModuleDecouple Decoupling Operations Stock
KASModuleContainer Containers KAS / Kerbal Assembly System
KASModuleGrab KAS / Kerbal Assembly System
KASModuleStrut KAS / Kerbal Assembly System
TweakScale Changing the size of parts TweakScale
MechJebCore Automated ship controls and advanced information systems MechJeb
ModuleConnectedLivingSpace MKS/OKS / Modular Kolonization System
KolonyConverter MKS/OKS / Modular Kolonization System
MKSModule MKS/OKS / Modular Kolonization System
ExWorkshop MKS/OKS / Modular Kolonization System
KarboniteAtmoExtractor MKS/OKS / Modular Kolonization System
KarboniteDrill MKS/OKS / Modular Kolonization System
KarboniteGenerator MKS/OKS / Modular Kolonization System
KarboniteParticleExtractor MKS/OKS / Modular Kolonization System
KarboniteConverter MKS/OKS / Modular Kolonization System
USI_Converter MKS/OKS / Modular Kolonization System
USIAnimation MKS/OKS / Modular Kolonization System
USI_BaseAnchor MKS/OKS / Modular Kolonization System
USI_InertialDampener MKS/OKS / Modular Kolonization System
ProxyLogistics MKS/OKS / Modular Kolonization System
FSanimateGeneric Firespitter
FStextureSwitch2 Firespitter
FSfuelSwitch Firespitter
MKSLcentral MKS/OKS / Modular Kolonization System
ORSModuleAirScoop MKS/OKS / Modular Kolonization System
ORSModuleAirIntake MKS/OKS / Modular Kolonization System
ORSResourceScanner MKS/OKS / Modular Kolonization System
ORSModuleRailsExtraction MKS/OKS / Modular Kolonization System
ORSModuleParticleCollector MKS/OKS / Modular Kolonization System
ORSAnimatedScanner MKS/OKS / Modular Kolonization System
ORSAnimatedExtractor MKS/OKS / Modular Kolonization System
ModuleSPU Remote Tech
ModuleRTAntennaPassive Remote Tech
FSplanePropellerSpinner Firespitter
FSengineSounds FSengineSounds


Internal specifies the internal files used to construct views from the IVA or internal vehicular activity, and are referenced out to the \Spaces\ directory of the relevant part mod. (Squad's internals are in \GameData\Squad\Spaces). INTERNALs have their own .cfg files with their own calls and methods that will not be discussed here. Squad provides 9 INTERNALs as part of Stock KSP:

  • crewCabinInternals
  • cupolaInternal
  • GenericSpace1
  • GenericSpace3
  • landerCabinInternals
  • landerCabinSmallInternal
  • mk1CockpitInternal
  • mk1PodCockpit
  • PodCockpit


In parts files, [RESOURCE] refers to a resource that is stored by a part. Each stored resource must be separately defined by a [RESOURCE] call. Any resource may be stored, including those not defined. The examples in the table below comes from a battery config.

variable example explanation
name ElectricCharge Name of the resource being stored.
amount 100 Amount of the resource included when dragged out of the parts list.
maxAmount 100 Maximum amount of the resource that can be stored
isTweakable false Allows/prevents modification of resource levels in editor.
hideFlow true Allows/prevents display of motion of resource transfer. Not sure why this would be important.


variable explanation
clip specifies the location of an audio clip to play during the specified thrust effect.

?? 2-part array, used twice, once to specify a minimum volume, once to specify a maximum volume, relative to the game's volume settings


?? 2-part array, used twice, once to specify a minimum volume, once to specify a maximum volume, relative to the game's volume settings


boolean, true or false, specifies whether to play the sound once, or to keep playing the sound as long as the specified effect is in operation

Resource Configuration Files

Resources are massively modifiable, but Stock KSP only comes with a few, and these are contained in squad/resources/ResourcesGeneric.cfg. Be extremely careful when modifying ResourcesGeneric.cfg, as it could have unintended side effects for your rockets. Resource definitions follow these conventions:

variable example explanation
Resource Mod
LiquidFuel Stock
Oxidizer Stock
SolidFuel Stock
MonoPropellant Stock
XenonGas Stock
ElectricCharge Stock
IntakeAir Stock
EVA Propellant Stock
MechanicalParts MKS/OKS
Recyclables MKS/OKS
ElectronicParts MKS/OKS
PlasticParts MKS/OKS
ModularParts MKS/OKS
ReplacementParts MKS/OKS
RepairKits MKS/OKS
PatchKits MKS/OKS
Computers MKS/OKS
Robotics MKS/OKS
ExoticMinerals MKS/OKS
RareMetals MKS/OKS
Chemicals MKS/OKS
Polymers MKS/OKS
SpecMachinery MKS/OKS
AdvMachinery MKS/OKS
BasicMachinery MKS/OKS
PunchCards MKS/OKS
Compost MKS/OKS
MEP-Manufacturing MKS/OKS
MEP-Laboratory MKS/OKS
MEP-Refining MKS/OKS
MEP-Environmental MKS/OKS
MEP-Computing MKS/OKS
This is the name of the resource. Like the name of your part, it is restricted to one word with no spaces or underscores. This is how the resource is referred to in-game.
Display Name Liquid Fuel Display name for UI elements, can have spaces.
Abbreviation LF For KerbNet resource switcher button. Two characters at best, like in the Periodic Table. Only important for things that are drilled up.
density 0.005 [density] is a numerical value between 0 and 1 used in calculations involving mass, storage capacity and units. Lower values mean lower densities, meaning you can get more units in a smaller space.
unitCost 0.8 [unitCost] defines the amount of Kerbits of value for each unit of the specified resource. Any number will do. Positive values indicate that you pay for the resource. Negative values have not been tested (yet), but it is assumed that negative values mean others will pay you to get rid of this resource. (Nuclear waste disposal, anyone?)
hsp 2010 Specific Heat, how much energy in joules per kelvin needed to raise the temperature of 1kg of resource by 1 deg Kelvin. High numbers make it great as a thermal control substance.
[flowMode] defines how the resource moves throughout your vessel whenever the resource is requested by a particular part. There are 4 known methods of flow mode:
  • PUMP
  • NONE
[transfer] is an optional method which specifies how and whether or not a resource may be manually transferred from one location on a vessel to another. There are two known methods of [transfer]:
  • true
  • false
[isTweakable] is an optional, boolean method which specifies whether or not a resource may be assigned during construction. Defaults to true. The only accepted arguments are true and false.
  • true
  • false
boolean, Is the gauge for this even ever visible (resource panel in flight and in VAB)? Overrides isTweakable. Almost every resource has this true.


Standard value is 1. How many litres of space a unit of this occupies. Affects tankage in volume sensitive storage systems like KIS and B9 Part Switch.

Science Definitions Configuration Files

variable example explanation
id crewReport internal name of the experiment in question
title Crew Report Flavor text of the experiment
baseValue 5 Base science value of the experiment
scienceCap 5 Max? value of the experiment, before multipliers
dataScale 1 Multiplier used in calculations
  • True
  • False
specifies whether this experiment must be conducted inside an atmosphere
situationMask 63 uses the sum of the situation bits to determine where the experiment can be conducted:
  • SrfLanded = 1,
  • SrfSplashed = 2,
  • FlyingLow = 4,
  • FlyingHigh = 8,
  • InSpaceLow = 16,
  • InSpaceHigh = 32
biomeMask 7 uses the same pattern as situationMask to determine whether experiment will give different result for different biomes. i.e. 7 = 1 + 2 + 4 so flying high will have only a single result per body but flying low (and landed or splashed) will give one result per biome
requiredExperimentLevel 0.5 specifies the level of research facility required before the experiment can be conducted
name example definition
Too many to list!
  • default
  • MohoSrf
You ran an Atmosphere Analysis, recording various measurements like temperature, pressure and atmosphere composition Flavor text for the science popup window and science archives that describes what happened when the experiment was conducted.
an array of data that provides flavor text for each scenario that the experiment is conducted in. Left side is a combination of the planet name and the situation bit. No spaces. Right side is the flavor text provided to the GUI.

Contracts Definitions Configuration Files

Contains a single call to STORY_DEF, which then allows for subsets
variable example explanation

Contracts Configuration Files

Agent Configuration Files

Agent configuration files specify specific Agents that may have an impact on the performance (read science, money, and prestige) awarded to your Kerbals for completion of specific tasks. Also specifies agency relations to one another. Many of these configurations are not implemented as of [0.90]

// Agency mentalities
// * Commercial   [Increased financial stakes, both for success and failure]
// * Competitive  [competes with companies which we have a negative standing towards, auto-added if any standings set][not impl]
// * Conglomerate  []
// * Startup   []
// * Cooperative  [not impl]
// * Ecomental   [not impl]
// * Economic   []
// * Hasty    [-deadlines -expiry +rep]
// * Patient   [] 
// * Industrial   [not impl] 
// * Perfectionist  [not impl]
// * Pioneer   [Makes agency more likely to offer a contract to something that's never been done before]
// * Record    [Flags agency as a record-keeping organization, focuses on contracts about breaking existing records and doing new things]
// * Scientific   [Agency is more likely to offer science data gathering contracts][not impl]
// * Stern     [Higher Reputation Stakes for both success and failure]
// * EasyGoing   [Lower Reputation Stakes for both success and failure]
// * Kerbalminded  [not impl][Sets up conditions against losing Kerbals]
// * Moral          [not impl]
// syntax guidelines
// standings = agent name string, float
// mentality = MentalityClass [float]

Kerbal Configuration Files

Defines what your Kerbals can do. Contained in the Traits.cfg file.

variable example definition in code
  • Pilot
  • Engineer
  • Scientist
describes the Kerbal's job
name = Pilot
title Any text Flavor text of the job
 title = Engineer 
desc Any text Flavor text of job description
desc = Pilots provide assistance in flying the vessel.
EFFECT { Array of skills describes benefits to vessel for having a Kerbal with this job aboard
  name = VesselScienceReturn
  modifiers = 1.05, 1.1, 1.15, 1.2, 1.25
  name = PartScienceReturn
  modifiers = 1.05, 1.1, 1.15, 1.2, 1.25

Prop Configuration Files

Contained in several different files, usually labeled prop.cfg, in the /Props/ directory. Describes aspects of parts used on IVAs, included buttons, switches, dials, and screens.

  name = directionalKnob
    name = internalGeneric
proxy = 0, 0, 0,  0.0225, 0.0075, 0.0225,  0, 1, 0

  name = RadarAltimeter
    name = InternalRadarAltitude
    indicatorName = indicator
       inc = 0, 0
       inc = 34, 100
       inc = 70, 200
       inc = 110, 300
       inc = 145, 400
       inc = 180, 500
       inc = 215, 1000
       inc = 232, 2000
       inc = 250, 3000
proxy = 0, 0, 0,  0.06, 0.01, 0.06,  1.0, 0.5, 0
  name = NavBall
    name = InternalNavBall
    navBallName = NavSphere
    iconUp = 0, 1, 0
    progradeVectorName = progradeVector
    retrogradeVectorName = retrogradeVector
    progradeWaypointName = progradeWaypoint
    retrogradeWaypointName = retrogradeWaypoint
 normalVectorName = NormalVector
 antiNormalVectorName = antiNormalVector
 radialInVectorName = RadialInVector
 radialOutVectorName = RadialOutVector
 maneuverArrowName = ManeuverArrow
 anchorName = Anchor
proxy = 0, 0, 0,  0.075, 0.01, 0.09,  1.0, 0.5, 0
  name = switch
    name = internalGeneric
proxy = 0, 0, 0,  0.0225, 0.0075, 0.0225,  0, 1, 0

Internals Configuration Files

Strategies Configuration Files

Contained in Strategies.cfg, used to describe the variable strategies available. Each strategy opens with STRATEGY {

variable samples description in code
  • AppreciationCampaignCfg
  • FundraisingCampaignCfg
  • OpenSourceTechProgramCfg
  • UnpaidResearchProgramCfg
  • OutsourcedResearchCfg
  • PatentsLicensingCfg
  • AgressiveNegotiations
  • RecoveryTransponders
Internal Description of Campaign Name. No spaces or special characters
name = AppreciationCampaignCfg
title Recovery Transponder Fitting Flavor text for the campaign name
title = Appreciation Campaign
desc Recovering parts landed far away from the Space Center can be very costly, but I reckon we can reduce those costs by installing better transponders on the parts we launch. These units are not cheap, but they should make it much easier to find parts, improving the recovery value even if they're half-way around Kerbin. What do you say? Flavor text for the description of the campaign
desc = We could definitely improve our 
image by putting some effort into reminding Kerbals 
everywhere of just how great the Space Program is. 
Advertisement space isn't free, however.
  • Operations
  • Finances
  • Science
  • Public Relations
Specifies the Department that the strategy belongs to. Can only be a department that already exists (as of [0.90]
department = Public Relations
icon specifies the icon image to be used in conjunction with the campaign. In the campaign selection.
icon = Squad/Strategies/Icons/AppreciationCampaign
  • Basic,A
  • Basic,B
  • Basic,C
  • Misc,D
  • Misc,Recovery
Uncertain, clearly has something to do with grouping
groupTag = Basic,A
minLeastDuration positive Integers the minimum shortest amount of time (in days) that the campaign may have (campaigns must run at least this long)
minLeastDuration = 60
maxLeastDuration positive Integers the maximum shortest amount of time (in days) that the campaign may have. Using the sliders, campaigns may be adjusted to require at least this long to run
maxLeastDuration = 100
minLongestDuration positive Integers the minimum longest duration (in days) of the campaign. Using the sliders, campaigns may be adjusted to only run this long
minLongestDuration = 1200
maxLongestDuration positive Integers the maximum longest duration (in days) of the campaign (campaigns cannot run longer than this)
maxLongestDuration = 1600
requiredReputationMin Integers Minimum reputation required to purchase this campaign
requiredReputationMin = -500
requiredReputationMax Integers The most reputation you can be required to have in order to run this campaign
requiredReputationMax = 750
initialCostFundsMin Integers Minimum funds required to purchase this campaign
initialCostFundsMin = 8000.0
initialCostFundsMax Integers The largest amount of Kerbits that can be required to purchase this campaign
initialCostFundsMax = 160000.0
initialCostReputation Integers Minimum cost in reputation to run this campaign
initialCostReputation = 0.0
initialCostScience Integers Minimum cost is science points to run this campaign
initialCostScience = 0.0
  • True
  • False
Can the campaign be adjusted by increasing inputs and getting greater outputs out of the campaign?
hasFactorSlider = True
factorSliderDefault Float multiplication factor for each step along the slider bar
factorSliderDefault = 0.05
factorSliderSteps Numbers number of steps/stages in the slider bar
factorSliderSteps = 20
EFFECT { see table below describes what the particular campaign actually does see table below


There are currently three different EFFECT types available for use in Strategies: CurrencyOperation, ValueModifier, and CurrencyConverter. Each one has different variables and are detailed below.

variable samples description in code
  • CurrencyOperation
internal reference name
name = CurrencyConverter
  • Funds
input and output for campaign operations
currency = Funds
  • Multiply
  • Add
operation to perform on currency
operation = Multiply
effectDescription "to Launch Costs" Flavor text for the operation to be performed
effectDescription = to Launch Costs
minValue Float factor to use in operations
minValue = 1.1
maxValue Float factor to use in operations
maxValue = 1.06
  • VesselRollout
  • RnDPartPurchase
conditions that trigger the operation
AffectReasons = VesselRollout
variable samples description in code
  • ValueModifier
internal reference name
name = CurrencyConverter
valueID VesselRecoveryFactor Value to be modified
valueId = VesselRecoveryFactor
minValue Float factor to use in operations
minValue = 1.1
maxValue Float factor to use in operations
maxValue = 1.06
variable samples description in code
  • CurrencyConverter
internal reference name
name = CurrencyConverter
  • Funds
  • Reputation
  • Science
specifies the input for the campaign
input = Funds
  • Reputation
  • Funds
  • Science
specifies the outputs for the campaign
output = Reputation
minShare Float specifies the minimum
minShare = 0.0
maxShare Float specifies the maximum
maxShare = 1.0
minRate Float specifies the minimum rate of conversion, based on slider values
minRate = 0.041667
maxRate Float specifies the maximum rate of conversion, based on slider values
maxRate = 0.0520
  • ContractReward
  • ScienceTransmission
  • ContractAdvance
  • VesselRecovery
  • VesselRollout
  • RnDPartPurchase
criteria for conversions
AffectReasons = ContractReward, ContractAdvance
  • gains
  • Income
describes the type of return
effectDescription = Income

Department Configuration Files

Used in the Strategies system, these specify the Departments available that provide different strategies for use.

variable samples description in code
  • Finances
  • Science
  • Public Relations
  • Operations
The department name
name = Public Relations
desc Flavor Text describes the department
desc = Linus is Wernher Von Kerman's Intern. 
Because Wernher himself is too important to be 
bothered with these boring strategy meetings. 
He sends his intern in his stead.
color array of 3 numbers between 0 and 255 specifies the color of the department
color = 149 254 135
  • Strategy_MechanicGuy
  • Strategy_PRGuy
  • Strategy_ScienceGuy
  • Strategy_Mortimer
Internal name of the Department Head
avatar = Strategy_PRGuy
  • Mortimer Kerman
  • Linus Kerman
  • Walt Kerman
  • Gus Kerman
Flavor Text for the Department Head
headName = Walt Kerman
animation file name for the Head shot of the Department Head featured in the strategy selection screen
headImage = PRGUY_KERMAN