I've been thinking about this idea for a while myself and decided to look for a thread about it before making a request of my own, which brought me here. I notice it's been a while since the last post in this thread and would be interested to know if any progress has been made. An interesting mechanic I noticed in this game a while ago, was that if you have a ship in orbit somewhere with most of it's fuel spent, and you then use Hyper Edit to instantly refill all the fuel, you're ship experiences a sudden decrease in velocity as the forces of gravity pull harder on your ship due to the substantial new mass you've just cheated in. Seeing this effect reminded me of a Sci-Fi series in which spaceships tend to slow down rapidly without the use of reverse thrusters or something similar. I always thought of this as the writers neglecting certain aspects of physics in favor of providing a better spectacle. But then I thought about it, and the series does use Inertial Dampners as an excuse for a large number of things. So I realized that if they turned off or turned down their Inertial Dampner systems, it would in fact cause the ship to slow down without having to use reverse thrusters. I don't know if the writers actually went by that idea(it's likely they didn't based on their track record of other things in the series), but it does work out. The Inertial Dampners reduce the mass of the vessel, and so by reducing their effect the vessel would gain mass and experience a greater pull from gravity. Why they turn down the Inertial Dampners at certain arbitrary points, as well as any kind of direct correlation between mass of the ship, it's speed, and nearby celestial bodies that would be exerting meaningful gravitational force are never addressed at all. So if they have the technology for Inertial Dampners, then I can forgive them some aspects of their depiction of space travel, of course a lot of Sci-Fi series tend to gloss over the more technical details of their technology because it wouldn't appeal to most people. I'm not talking about waving the magical science wand, but actual theoretical or actual concepts they could have used to explain certain technologies. Anyways, I went off on a tangent there. The point is. I'd really like to see an Inertial Dampner mod in KSP, something that reduces the overall mass of the entire vessel it's attached to in proportion to how much energy is used. Also, if you add it to the Intersellar mod tech-tree, I think it should come after Warp Drive research, or at the same time if you can't extend the tree further easily. Afterall, in real life there are some possible theories for warp-drives, but to the best of my knowledge, Inertial Dampners as seen in Science Fiction are still very much in the "completely magical" part of sci-fi technologies.