Inertia Dampeners
The Inertia Dampeners are automatic controls built into all propulsion systems that allow ships or jetpacks to be flown in a manner more intuitive to Engineers used to the pull of drag and gravity. They can be toggled on or off by pressing the 'Z' key by default.
When switched on, jetpacks and ships will automatically attempt to reduce velocity to 0 in all directions that do not currently have a manual control activated; e.g. if the player is not holding down 'W' to move forward, then the reverse thrusters will automatically deploy to reduce forward velocity to 0.
Wise use of the dampeners is essential to becoming a good pilot. Dampeners should be toggled off on long journeys to save on the fuel of constant forward movement, and should be switched on when attempting to maneuver tight spaces. Engineers that prefer a more realistic option may choose to leave them off permanently.
It should be noted that dampeners, being programmatically controlled, have complete use of thruster capacity under their control. Manually-fired thrusters and jetpacks only fire at 75% maximum capacity. This means that when coming to a stop, it is faster to activate inertia dampeners and release all controls than to manually fire in reverse. This can mean the difference between scratching the paint and shearing your ship in half, so be aware of it.