Physicsless part
Some parts within the game are listed as having a small mass, but in the config file a flag is set "PhysicsSignificance = 1". This has the effect that in flight physics calculations such as mass and drag are not calculated for that part. When constructing a craft, the root part can't be such a part.
Behaviour
A craft with only massless parts starts to oscillate after a short time and then starts to destroy itself. But this is usually not possible because the root part is always not a massless part. The game can change the property on the fly, because when a new root part after decoupling would be massless the game removes that special status.
List of massless parts
Parts with PhysicsSignificance = 1 as of 0.24.2
- 2HOT Thermometer
- BZ-52 Radial Attachment Point
- Communotron 16
- Communotron 88-88
- Cubic Octagonal Strut
- Double-C Seismic Accelerometer
- FL-A5 Adapter
- GRAVMAX Negative Gravioli Detector
- Illuminator Mk1 (spot)
- Illuminator Mk2 (wide)
- O-10 MonoPropellant Engine
- Octagonal Strut
- OX-STAT Photovoltaic Panels
- Pegasus I Mobility Enhancer
- Place-Anywhere 7 Linear RCS Port
- PresMat Barometer
- RV-105 RCS Thruster Block
- Small Hardpoint
- Telus-LV Bay Mobility Enhancer
- Telus Mobility Enhancer
- TR-38-D (Size 3 decoupler)
- Vernor Engine
- Z-100 Rechargeable Battery Pack
- Z-400 Rechargeable Battery
Parts that are massless due to their part type, but do not have the PhysicsSignificance flag set
Note that the LT-2 Landing Strut has PhysicsSignificance = 0 in its part.cfg. This does nothing, and the part behaves as normal.
See also
- “Kerbal Space Program - Your Physics Have No Power Over Me!” by Scott Manley
