Inertial Drives and Gravimetric Engines

http://www.b5tech.com/misctech/engines/gravimetric/gravimetric.html

The term “inertial drive” I have taken from ‘3001: Final Odyssey’, presumably the correct term would be “negative-inertial drive” but that’s a bit of a mouthful. Anyway, the above link describes, roughly, how they would work and how they would be more efficient than regular ion or plasma drives.

I would suggest, however, that there are two or three possible types of inertial drives, all of which can be seen in ‘Babylon 5’ (in most televised and filmed science fiction, pretty much everyone uses ion drives, although anti-gravity is sometimes shown. The transport tubes used in the “New New York” of ‘Futurama’ use inertial drives as people are shown traveling in any direction).

The first, “true”, inertial drive is clearly used by the Minbari in all their warships, flyers and fighters. These craft do not actually accelerate, they have a constant velocity determined by their apparent “acceleration”. What this means in layman’s terms, as I can’t quite explain it any other way, is that Minbari vessels can have massive amounts acceleration (maybe a million g) but they do not actually accelerate and, as they have no inertia, any body they impact with will only impact with the momentum of that body, neither will every Minbari be crushed if the ship they are on stops suddenly. This is a bit like walking, as opposed to running, into a wall. Which would hurt more? Now imagine that you could traverse the same distance in the same amount of time by walking as by running. The advantages in warfare are obvious.

The next two work on similar principles and are indistinguishable on observation alone. These are what I would refer to, quoting Babylon 5, as gravimetric drives (although the terms really are interchangeable). They are seen being used by the Centauri, the White Stars utilize them as does the “Excalibur” and the alien warships seen in the ‘Crusade’ episode “The Needs of Earth”, as all these ships use ion drives to maintain forward velocity but are much more maneuverable than ion drive-reliant vessels.

The first type cancels all forces, such as gravity, that would force a space ship to change direction except in the direction intended. Even without ion engines a ship would accelerate, although much slower, due to the effects of gravity and virtual particles. Centauri warships and Technomage ships are examples of this type.

The second type is dependent on an ion drive to change direction as that kind of gravimetric drive works to place a vessel stationary with respect to the expansion of the universe, its orbit around the galactic core and any stellar body. A la “The Planet Express Ship” in ‘Futurama’, it is not the ship that moves it is the rest of the universe! The White Stars do seem to employ this method as the main use of their ion engines appears to be to maneuver as quickly as a Starfury, executing a 180 degree spin in about two seconds with the gravimetric drive still engaged.