Inertia dampeners are a game mechanic that relates to both the player's jetpack as well as a ship's thrusters. When dampeners are enabled, if there is no player input on a certain thruster axis (for instance, the player is thrusting forward along the X axis by holding "W", which activates aft thrusters and keeps bow thrusters off, and leaves zenith/"up" and nadir/"down" (Z axis) and port/left and starboard/right (Y axis) thrusters), the thrusters on the remaining axes will attempt to cancel out velocity on these axes.
In practice this means that the ship or character do not retain velocity in the direction not desired by the player and, if the player is not firing any thrusters, they stop automatically. Since most players use Gyroscopes to orient their ships towards their desired direction, and accordingly outfit them with large banks of aft thrusters, the natural action would be to point their bow towards the target, and thrust forward. However, the player would first have to either cancel out their existing velocity (stop), or aim for the sum of existing and added velocity vectors to point into the direction of their target - complicated, since it requires aiming into a direction considerably different from the target, but not impossible. Inertial dampeners automatically eliminate the undesired component of velocity automatically while underway, resulting in a minor "skid".
In even simpler terms, inertial dampeners keep the ship from going in the directions you're not currently thrusting in.
Inertia dampeners fire thrusters at above their normal power, minimizing the "skid".
To toggle the inertial dampening in a ship the player must be in a cockpit and press the z key; this toggle will stay even after the player exits the cockpit. If a player turns off inertial dampeners in a cockpit, when they exit theirs will be turned off as well, as to avoid complications with runaway ships.
In the newest update, 1.188 Keen added a feature. While in a small grid or, a suit, look at a large ship and press Crtl + Z. This will activate "Matching Dampeners". This setting allows you to fly outside of a ship while it is moving because you match speed with the larger vessel.
Use in ship design
While the player's jetpack has thrusters in all directions and therefore has fully functioning inertia dampening at the beginning of the game, a player will need to add at least one thruster to each of the 6 faces of the ship for complete inertia dampening. For example, if a player only has thrusters pointing down on the bottom of the ship, there would only be dampening when the ship travels in the "down" direction; if the ship is traveling "down" and "forward" then the thrusters would cancel out the downward movement but not the forward movement.
While it is possible to stop with incomplete thruster coverage, this is usually required as a result of damage, as it eliminates the convenience of dampeners.
Use in gameplay
Generally, the inertia dampeners should be turned to on. The activation of the inertial dampeners makes handling of your ships or engineer easier, as the activation of the counter thrusters is automatic. Please bear in mind that the use of inertial dampeners makes braking only somewhat easier, as it still depends on the performance of your counter thrusters and the current speed of your ship or engineer. While small fighters have little problems stopping, larger ships can often "skid" for kilometers.
For players that want the more "realistic" feel, turning off the inertial dampeners is a good idea.
Manipulations with Dampeners
There is a great variety of situations that don't require dampening:
- Long range flights: after you reach maximum velocity, you are forced to thrust forward to maintain that speed - which is pure waste of uranium. A far more efficient procedure is to thrust to comfortable velocity, switch dampeners off, coast into range of target, and only at that point the dampeners are reactivated for a braking burn;
- Minimizing thruster damage on takeoff: with dampeners off, only a brief engine burn is required to gently get out of thruster damage range of the pad - instead of burning continuously, which puts gaping holes into Light Armor Blocks;
- Carrier operations: a ship with dampeners on will be trying to stop the mothership it's docked to, which can easily result in loss of control and damage, or a sudden collision with the rear bulkhead as soon as the fighter unlatches;
- Flying a heavily damaged ship back to base using the only surviving thruster, and landing it without scratching the landing pad's paint (bonus bragging rights if said thruster is on the top, but the pilot still manages to touch down softly with the correct orientation);
- Stationkeeping near other moving vessels;
- Rapid retroburns with rear thrusters: instead of slowly braking with the usually rudimentary bow thrusters, a ship can be flipped over and only then engage the dampeners, rapidly grinding to a halt;
- Retaining velocity: a dampening ship constantly tries to loose velocity, which is a bad thing if one is under fire;
- Target-leading mind-screw: since most players instinctively consider the target to be moving in the direction of its bow (Archimedean motion), a dampeners-off ship that exploits Newtonian physics can confuse many human opponents, and is genuinely unpredictable;
- Engage targets with fixed weapons at any deflection without changing velocity: a dampeners-off craft can spin about and shred any hostile, especially one following it.