StarDestroyer.Net BBS

Okay almighty technical geniuses of SDN:

I'm writing a fic that takes place in our solar system, except the Earth has been utterly destroyed (reduced to space rubble by some cataclysm)

The human civilization that has survived is currently in the middle of a lot of feuding between rival warlords. I just need some help coming up with methods of locomotion about the post-apocalyptic solar system. Here are my ideas.

Chemical rockets:
used to get off of planets/planetoids/moons, etc because they have a lot of thrust. They are, of course, pathetically slow when it comes to going great distances.

Nuclear engines:
use of a nuclear reactor to heat plasma and spit it out the ass end. This is what Discovery used in 2001: A space oddesy, by Arthur C. Clarke

Fusion engines
use a fusion reactor to heat up plasma and squirt it out the back. A little more technical, and so much rarer among deep space warlords.

Ion engines:
ionizes a charge of xenon gas (what about other gasses that might be easier to come by in the post apocalyptic solar system, such as hydrogen or oxygen?) and uses electrical fields to guide it out the back of the nozzle and propel the ship forward.

Projectile: (???)
magnetic accelerators are common weapons, so what about utilizing one to propel debris out one end of the ship, while the rest of the ship goes in the other?

Hybrid: (???????????????????????)
This one I'm not too sure about. Would it work to burn hydrogen and oxygen like a chemical rocket, and utilize an ion drive at the same time, exciting the resulting vapor to further accelerate it's exit, or would this just be a waste of time/effort/energy, and money, all of which a warlord is typically short on in the PASS?

Anti-matter:
not used, tech above 31st century PASS.

Nuclear engines or fusion torch drives sound like the best solution. Chemical rockets and ion engines are so slow it would take years to get between planets, and the projectile idea just doesn't sound practical.

That's about what I was thinking. But I thought ion engines were supposed to be fast (well, ten times faster for a given weight of propellant, supposedly). Just that they have so little thrust it takes a long time for them to accelerate up to this high speed.

edit:

Erk... ten times as fast as chemical rockets, that is...

I've thought of using magnetic accelerators as "afterburners" to increase the thrust provided by fusion rockets. That might work as a hybrid.

Overall, I think your best bet would be fusion rockets, because radioactive fuels-- e.g., that used by nuclear fission rockets-- are not only dangerous to the human crew, they're also hard to find, excavate, process, etc. The hydrogen used by a fusion rocket would be much easier to find-- put harvesters on gas planets, or extract them from oceans, etc.

You can keep magnetic accelerators as "slingshots" to get small spacecraft off planets/out of a solar system for low cost. It's impractical for large spacecraft, though.

The fusion engine, or plasma engine, seems ok. You can have an 'afterburner' effect by flowing raw fuel past or near the reactor to flash it to plasma for an extra boost, though obviously you'll tear through fuel quick.

Another idea, solar sails. No, not huge actaul sails, but there is the mag sail concept or even better the M2P2 that could work in concert with a plasma engine.