I'm feeling like a Quixote type character in pursuit of hard science fiction Traveller space opera instead of windmills. So far I've examined a variety of different options, some offer to solve the problem by throwing out half or more of existing Traveller works (adventures and such), others just don't make the bar for one reason or another, still others may require quite a bit of work refactoring trade and commerce even the value of a credit, finally there are a few that would sort of work but for one reason or another I just don't like. My last post concerned one such option, basically redefining the Traveller Jump drive operation to allow for the wilderness option. I'm still unsure as to the side effects of that option and it allows for the 'go anywhere' ftl style I really don't like.
Once again I'm drawn back to the Lares fixed point ftl and keyhole drive option. Accepting a certain degree of increased travel times and interface costs seems unavoidable. While earlier I examined the options of extending the handwave of ftl into a sort of slow stutterwarp or fast microjump those solutions felt clumsy. One option I've avoided examining very closely is that of extracting the underlying whatchamacallit in the handwavium ftl, defining its effects, and extending it to other technologies such as reaction drives. Traveller does this with practically every handwavium technology and also shows the pitfalls inherent in doing so; chief among them the tendency for handwavium creepage leading to setting domination.
I've discussed this with a friend who pointed out that extending the handwavium to incorporate the core technology whatchamacallit of the game Mass Effect would solve most of the problems. While I don't disagree that it is an option, I don't like the direction it leads. However, while considering it, I did think a bit about the handwavium of the Quantum Skip drive. The basic idea is that using a rather large but extremely short pulse of energy in a controlled fashion we somehow are able to distort the local frame of space time and trigger a quantum effect that does the actual work. Might earlier experiments along those lines have been aimed at increasing reaction drive Isp?
Now at some absurd tech level with 99.99% efficiency we might create a drive with an Isp as high as 2.93966571 × 109 or 816,573.8 G-hours of thrust per ton of fuel.. yeah. Of course even with 99.99% efficiency, generating any significant amount of thrust would require our ship to basically be all radiator to avoid vaporizing moments after engine ignition. The stock answer to the Isp, thrust, and heat issues seems to be either ignore it altogether or assume some handwavium to allow heat levels in the engine that would vaporize any known material nearby instantly.
Looking back to the math hacking I did the other day in 'An Ode to Simplicity', we can see that extending travel time for the trip between planetary orbit and ftl point to around two weeks each way brings us into the realm of plausible 3He2H magnetic bottle fusion engines. Well plausible to some. Call me cynical but we've seen fusion power as being on the near horizon for forty years now and really we don't seem to be much closer than we were shortly after starting. Then consider that turning a magnetic bottle fusion reactor into a rocket engine is at least one hundred times more challenging in engineering.
The next 'breakpoint' seems to come at around 49 days each way, with 0.05 m/s^2 of thrust as we could reasonably expect from an advanced magnetoplasmadynamic drive. Each transit would require about 212.1km/s delta-V, so to meet our 50% fuel load requirement we'd need an Isp of about 61200 which could also possibly be expected from the same drive. I like this point except 49 days is nearly 50% over what I'd really want to see as the maximum average.
My ideal drive would have a 27 day transit time (x2 = 54) and the same 50% fuel load requirement. This would require a constant acceleration of 0.17 m/s^2, a delta-v of 386km/s per transit, and an Isp of around 112000. This is a substantial improvement over our advanced magnetoplasmadynamic drive and may be past the capabilities of even advanced technologies based on known physics. On the other hand I have some oddball ideas, totally fictional of course, but what if you combined a NTR with a VASIMR? What if there was some quantum handwavium along the lines of the Quantum Skip drive technology that, in an earlier form, allowed some higher powered 'pulse mode' operation? At the same time, the acceleration/Isp requirements for this level of performance seem to be well within the range of plausible 3He2H magnetic bottle rockets.
Rather than get into detail about 'how it works', I could simply call it the standard deep space drive and let it go at that. That follows along with the idea in yesterday's post of packaging the interface engine into a simple to use drive package. I'll call it the AMPR (Advanced Magneto Plasma Rocket).
Now for combat purposes, what we really want is something like the interface drive minus the scramjet part, or simply the TANTR. A drive that gives us heaps of thrust for short periods of time with a decent (for high thrust engines that is) Isp. A plus to the use of a TANTR type engine for this purpose is that when not being used for thrust, it produces power.
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